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+\title Simon Tatham's Portable Puzzle Collection
+
+\cfg{winhelp-filename}{puzzles.hlp}
+\cfg{winhelp-contents-titlepage}{Contents}
+
+\cfg{text-filename}{puzzles.txt}
+
+\cfg{html-contents-filename}{index.html}
+\cfg{html-template-filename}{%k.html}
+\cfg{html-index-filename}{docindex.html}
+\cfg{html-leaf-level}{1}
+\cfg{html-contents-depth-0}{1}
+\cfg{html-contents-depth-1}{2}
+\cfg{html-leaf-contains-contents}{true}
+
+\cfg{info-filename}{puzzles.info}
+
+\cfg{ps-filename}{puzzles.ps}
+\cfg{pdf-filename}{puzzles.pdf}
+
+\define{by} \u00D7{x}
+
+\define{dash} \u2013{-}
+
+\define{times} \u00D7{*}
+
+\define{divide} \u00F7{/}
+
+\define{minus} \u2212{-}
+
+This is a collection of small one-player puzzle games.
+
+\copyright This manual is copyright 2004-2014 Simon Tatham. All rights
+reserved. You may distribute this documentation under the MIT licence.
+See \k{licence} for the licence text in full.
+
+\cfg{html-local-head}{<meta name="AppleTitle" content="Puzzles Help">}
+
+\C{intro} Introduction
+
+I wrote this collection because I thought there should be more small
+desktop toys available: little games you can pop up in a window and
+play for two or three minutes while you take a break from whatever
+else you were doing. And I was also annoyed that every time I found
+a good game on (say) \i{Unix}, it wasn't available the next time I
+was sitting at a \i{Windows} machine, or vice versa; so I arranged
+that everything in my personal puzzle collection will happily run on
+both, and have more recently done a port to \i{Mac OS X} as well. When I
+find (or perhaps invent) further puzzle games that I like, they'll
+be added to this collection and will immediately be available on
+both platforms. And if anyone feels like writing any other front
+ends \dash PocketPC, Mac OS pre-10, or whatever it might be \dash
+then all the games in this framework will immediately become
+available on another platform as well.
+
+The actual games in this collection were mostly not my invention; they
+are re-implementations of existing game concepts within my portable
+puzzle framework. I do not claim credit, in general, for inventing the
+rules of any of these puzzles. (I don't even claim authorship of all
+the code; some of the puzzles have been submitted by other authors.)
+
+This collection is distributed under the \i{MIT licence} (see
+\k{licence}). This means that you can do pretty much anything you like
+with the game binaries or the code, except pretending you wrote them
+yourself, or suing me if anything goes wrong. 
+
+The most recent versions, and \i{source code}, can be found at
+\I{website}\W{http://www.chiark.greenend.org.uk/~sgtatham/puzzles/}\cw{http://www.chiark.greenend.org.uk/~sgtatham/puzzles/}.
+
+Please report \I{feedback}\i{bugs} to
+\W{mailto:anakin@pobox.com}\cw{anakin@pobox.com}.
+You might find it helpful to read this article before reporting a bug:
+
+\W{http://www.chiark.greenend.org.uk/~sgtatham/bugs.html}\cw{http://www.chiark.greenend.org.uk/~sgtatham/bugs.html}
+
+\ii{Patches} are welcome. Especially if they provide a new front end
+(to make all these games run on another platform), or a new game.
+
+
+\C{common} \ii{Common features}
+
+This chapter describes features that are common to all the games.
+
+\H{common-actions} \I{controls}Common actions
+
+These actions are all available from the \I{Game menu}\q{Game} menu
+and via \I{keys}keyboard shortcuts, in addition to any game-specific
+actions.
+
+(On \i{Mac OS X}, to conform with local user interface standards, these
+actions are situated on the \I{File menu}\q{File} and \I{Edit
+menu}\q{Edit} menus instead.)
+
+\dt \ii\e{New game} (\q{N}, Ctrl+\q{N})
+
+\dd Starts a new game, with a random initial state.
+
+\dt \ii\e{Restart game}
+
+\dd Resets the current game to its initial state. (This can be undone.)
+
+\dt \ii\e{Load}
+
+\dd Loads a saved game from a file on disk.
+
+\dt \ii\e{Save}
+
+\dd Saves the current state of your game to a file on disk.
+
+\lcont{
+
+The Load and Save operations preserve your entire game
+history (so you can save, reload, and still Undo and Redo things you
+had done before saving).
+
+}
+
+\dt \I{printing, on Windows}\e{Print}
+
+\dd Where supported (currently only on Windows), brings up a dialog
+allowing you to print an arbitrary number of puzzles randomly
+generated from the current parameters, optionally including the
+current puzzle. (Only for puzzles which make sense to print, of
+course \dash it's hard to think of a sensible printable representation
+of Fifteen!)
+
+\dt \ii\e{Undo} (\q{U}, Ctrl+\q{Z}, Ctrl+\q{_})
+
+\dd Undoes a single move. (You can undo moves back to the start of the
+session.)
+
+\dt \ii\e{Redo} (\q{R}, Ctrl+\q{R})
+
+\dd Redoes a previously undone move.
+
+\dt \ii\e{Copy}
+
+\dd Copies the current state of your game to the clipboard in text
+format, so that you can paste it into (say) an e-mail client or a
+web message board if you're discussing the game with someone else.
+(Not all games support this feature.)
+
+\dt \ii\e{Solve}
+
+\dd Transforms the puzzle instantly into its solved state. For some
+games (Cube) this feature is not supported at all because it is of
+no particular use. For other games (such as Pattern), the solved
+state can be used to give you information, if you can't see how a
+solution can exist at all or you want to know where you made a
+mistake. For still other games (such as Sixteen), automatic solution
+tells you nothing about how to \e{get} to the solution, but it does
+provide a useful way to get there quickly so that you can experiment
+with set-piece moves and transformations.
+
+\lcont{
+
+Some games (such as Solo) are capable of solving a game ID you have
+typed in from elsewhere. Other games (such as Rectangles) cannot
+solve a game ID they didn't invent themself, but when they did
+invent the game ID they know what the solution is already. Still
+other games (Pattern) can solve \e{some} external game IDs, but only
+if they aren't too difficult.
+
+The \q{Solve} command adds the solved state to the end of the undo
+chain for the puzzle. In other words, if you want to go back to
+solving it yourself after seeing the answer, you can just press Undo.
+
+}
+
+\dt \I{exit}\ii\e{Quit} (\q{Q}, Ctrl+\q{Q})
+
+\dd Closes the application entirely.
+
+\H{common-id} Specifying games with the \ii{game ID}
+
+There are two ways to save a game specification out of a puzzle and
+recreate it later, or recreate it in somebody else's copy of the
+same puzzle.
+
+The \q{\i{Specific}} and \q{\i{Random Seed}} options from the
+\I{Game menu}\q{Game} menu (or the \q{File} menu, on \i{Mac OS X}) each
+show a piece of text (a \q{game ID}) which is sufficient to
+reconstruct precisely the same game at a later date.
+
+You can enter either of these pieces of text back into the program
+(via the same \q{Specific} or \q{Random Seed} menu options) at a
+later point, and it will recreate the same game. You can also use
+either one as a \i{command line} argument (on Windows or Unix); see
+\k{common-cmdline} for more detail.
+
+The difference between the two forms is that a descriptive game ID
+is a literal \e{description} of the \i{initial state} of the game,
+whereas a random seed is just a piece of arbitrary text which was
+provided as input to the random number generator used to create the
+puzzle. This means that:
+
+\b Descriptive game IDs tend to be longer in many puzzles (although
+some, such as Cube (\k{cube}), only need very short descriptions).
+So a random seed is often a \e{quicker} way to note down the puzzle
+you're currently playing, or to tell it to somebody else so they can
+play the same one as you.
+
+\b Any text at all is a valid random seed. The automatically
+generated ones are fifteen-digit numbers, but anything will do; you
+can type in your full name, or a word you just made up, and a valid
+puzzle will be generated from it. This provides a way for two or
+more people to race to complete the same puzzle: you think of a
+random seed, then everybody types it in at the same time, and nobody
+has an advantage due to having seen the generated puzzle before
+anybody else.
+
+\b It is often possible to convert puzzles from other sources (such
+as \q{nonograms} or \q{sudoku} from newspapers) into descriptive
+game IDs suitable for use with these programs.
+
+\b Random seeds are not guaranteed to produce the same result if you
+use them with a different \i\e{version} of the puzzle program. This
+is because the generation algorithm might have been improved or
+modified in later versions of the code, and will therefore produce a
+different result when given the same sequence of random numbers. Use
+a descriptive game ID if you aren't sure that it will be used on the
+same version of the program as yours.
+
+\lcont{(Use the \q{About} menu option to find out the version number
+of the program. Programs with the same version number running on
+different platforms should still be random-seed compatible.)}
+
+\I{ID format}A descriptive game ID starts with a piece of text which
+encodes the \i\e{parameters} of the current game (such as grid
+size). Then there is a colon, and after that is the description of
+the game's initial state. A random seed starts with a similar string
+of parameters, but then it contains a hash sign followed by
+arbitrary data.
+
+If you enter a descriptive game ID, the program will not be able to
+show you the random seed which generated it, since it wasn't
+generated \e{from} a random seed. If you \e{enter} a random seed,
+however, the program will be able to show you the descriptive game
+ID derived from that random seed.
+
+Note that the game parameter strings are not always identical
+between the two forms. For some games, there will be parameter data
+provided with the random seed which is not included in the
+descriptive game ID. This is because that parameter information is
+only relevant when \e{generating} puzzle grids, and is not important
+when playing them. Thus, for example, the difficulty level in Solo
+(\k{solo}) is not mentioned in the descriptive game ID.
+
+These additional parameters are also not set permanently if you type
+in a game ID. For example, suppose you have Solo set to \q{Advanced}
+difficulty level, and then a friend wants your help with a
+\q{Trivial} puzzle; so the friend reads out a random seed specifying
+\q{Trivial} difficulty, and you type it in. The program will
+generate you the same \q{Trivial} grid which your friend was having
+trouble with, but once you have finished playing it, when you ask
+for a new game it will automatically go back to the \q{Advanced}
+difficulty which it was previously set on.
+
+\H{common-type} The \q{Type} menu
+
+The \I{Type menu}\q{Type} menu, if present, may contain a list of
+\i{preset} game settings. Selecting one of these will start a new
+random game with the parameters specified.
+
+The \q{Type} menu may also contain a \q{\i{Custom}} option which
+allows you to fine-tune game \i{parameters}. The parameters
+available are specific to each game and are described in the
+following sections.
+
+\H{common-cmdline} Specifying game parameters on the \i{command line}
+
+(This section does not apply to the \i{Mac OS X} version.)
+
+The games in this collection deliberately do not ever save
+information on to the computer they run on: they have no high score
+tables and no saved preferences. (This is because I expect at least
+some people to play them at work, and those people will probably
+appreciate leaving as little evidence as possible!)
+
+However, if you do want to arrange for one of these games to
+\I{default parameters, specifying}default to a particular set of
+parameters, you can specify them on the command line.
+
+The easiest way to do this is to set up the parameters you want
+using the \q{Type} menu (see \k{common-type}), and then to select
+\q{Random Seed} from the \q{Game} or \q{File} menu (see
+\k{common-id}). The text in the \q{Game ID} box will be composed of
+two parts, separated by a hash. The first of these parts represents
+the game parameters (the size of the playing area, for example, and
+anything else you set using the \q{Type} menu).
+
+If you run the game with just that parameter text on the command
+line, it will start up with the settings you specified.
+
+For example: if you run Cube (see \k{cube}), select \q{Octahedron}
+from the \q{Type} menu, and then go to the game ID selection, you
+will see a string of the form \cq{o2x2#338686542711620}. Take only
+the part before the hash (\cq{o2x2}), and start Cube with that text
+on the command line: \cq{PREFIX-cube o2x2}.
+
+If you copy the \e{entire} game ID on to the command line, the game
+will start up in the specific game that was described. This is
+occasionally a more convenient way to start a particular game ID
+than by pasting it into the game ID selection box.
+
+(You could also retrieve the encoded game parameters using the
+\q{Specific} menu option instead of \q{Random Seed}, but if you do
+then some options, such as the difficulty level in Solo, will be
+missing. See \k{common-id} for more details on this.)
+
+\H{common-unix-cmdline} \i{Unix} \i{command-line} options
+
+(This section only applies to the Unix port.)
+
+In addition to being able to specify game parameters on the command
+line (see \k{common-cmdline}), there are various other options:
+
+\dt \cw{--game}
+
+\dt \cw{--load}
+
+\dd These options respectively determine whether the command-line
+argument is treated as specifying game parameters or a \i{save} file
+to \i{load}. Only one should be specified. If neither of these options
+is specified, a guess is made based on the format of the argument.
+
+\dt \cw{--generate }\e{n}
+
+\dd If this option is specified, instead of a puzzle being displayed,
+a number of descriptive game IDs will be \I{generating game IDs}invented
+and printed on standard output. This is useful for gaining access to
+the game generation algorithms without necessarily using the frontend.
+
+\lcont{
+
+If game parameters are specified on the command-line, they will be
+used to generate the game IDs; otherwise a default set of parameters
+will be used.
+
+The most common use of this option is in conjunction with \c{--print},
+in which case its behaviour is slightly different; see below.
+
+}
+
+\dt \I{printing, on Unix}\cw{--print }\e{w}\cw{x}\e{h}
+
+\dd If this option is specified, instead of a puzzle being displayed,
+a printed representation of one or more unsolved puzzles is sent to
+standard output, in \i{PostScript} format.
+
+\lcont{
+
+On each page of puzzles, there will be \e{w} across and \e{h} down. If
+there are more puzzles than \e{w}\by\e{h}, more than one page will be
+printed.
+
+If \c{--generate} has also been specified, the invented game IDs will
+be used to generate the printed output. Otherwise, a list of game IDs
+is expected on standard input (which can be descriptive or random
+seeds; see \k{common-id}), in the same format produced by
+\c{--generate}.
+
+For example:
+
+\c PREFIX-net --generate 12 --print 2x3 7x7w | lpr
+
+will generate two pages of printed Net puzzles (each of which will
+have a 7\by\.7 wrapping grid), and pipe the output to the \c{lpr}
+command, which on many systems will send them to an actual printer.
+
+There are various other options which affect printing; see below.
+
+}
+
+\dt \cw{--save }\e{file-prefix} [ \cw{--save-suffix }\e{file-suffix} ]
+
+\dd If this option is specified, instead of a puzzle being
+displayed, saved-game files for one or more unsolved puzzles are
+written to files constructed from the supplied prefix and/or suffix.
+
+\lcont{
+
+If \c{--generate} has also been specified, the invented game IDs will
+be used to generate the printed output. Otherwise, a list of game IDs
+is expected on standard input (which can be descriptive or random
+seeds; see \k{common-id}), in the same format produced by
+\c{--generate}.
+
+For example:
+
+\c PREFIX-net --generate 12 --save game --save-suffix .sav
+
+will generate twelve Net saved-game files with the names
+\cw{game0.sav} to \cw{game11.sav}.
+
+}
+
+\dt \cw{--version}
+
+\dd Prints version information about the game, and then quits.
+
+The following options are only meaningful if \c{--print} is also
+specified:
+
+\dt \cw{--with-solutions}
+
+\dd The set of pages filled with unsolved puzzles will be followed by
+the solutions to those puzzles.
+
+\dt \cw{--scale }\e{n}
+
+\dd Adjusts how big each puzzle is when printed. Larger numbers make
+puzzles bigger; the default is 1.0.
+
+\dt \cw{--colour}
+
+\dd Puzzles will be printed in colour, rather than in black and white
+(if supported by the puzzle).
+
+
+\C{net} \i{Net}
+
+\cfg{winhelp-topic}{games.net}
+
+(\e{Note:} the \i{Windows} version of this game is called
+\i\cw{NETGAME.EXE} to avoid clashing with Windows's own \cw{NET.EXE}.)
+
+I originally saw this in the form of a Flash game called \i{FreeNet}
+\k{FreeNet}, written by Pavils Jurjans; there are several other
+implementations under the name \i{NetWalk}. The computer prepares a
+network by connecting up the centres of squares in a grid, and then
+shuffles the network by rotating every tile randomly. Your job is to
+rotate it all back into place. The successful solution will be an
+entirely connected network, with no closed loops. \#{The latter
+clause means that there are no closed paths within the network.
+Could this be clearer? "No closed paths"?} As a visual aid,
+all tiles which are connected to the one in the middle are
+highlighted. 
+
+\B{FreeNet} \W{http://www.jurjans.lv/stuff/net/FreeNet.htm}\cw{http://www.jurjans.lv/stuff/net/FreeNet.htm}
+
+\H{net-controls} \i{Net controls}
+
+\IM{Net controls} controls, for Net
+\IM{Net controls} keys, for Net
+\IM{Net controls} shortcuts (keyboard), for Net
+
+This game can be played with either the keyboard or the mouse. The
+controls are:
+
+\dt \e{Select tile}: mouse pointer, arrow keys
+
+\dt \e{Rotate tile anticlockwise}: left mouse button, \q{A} key
+
+\dt \e{Rotate tile clockwise}: right mouse button, \q{D} key
+
+\dt \e{Rotate tile by 180 degrees}: \q{F} key
+
+\dt \e{Lock (or unlock) tile}: middle mouse button, shift-click, \q{S} key
+
+\dd You can lock a tile once you're sure of its orientation. You can
+also unlock it again, but while it's locked you can't accidentally
+turn it.
+
+The following controls are not necessary to complete the game, but may
+be useful:
+
+\dt \e{Shift grid}: Shift + arrow keys
+
+\dd On grids that wrap, you can move the origin of the grid, so that
+tiles that were on opposite sides of the grid can be seen together.
+
+\dt \e{Move centre}: Ctrl + arrow keys
+
+\dd You can change which tile is used as the source of highlighting.
+(It doesn't ultimately matter which tile this is, as every tile will
+be connected to every other tile in a correct solution, but it may be
+helpful in the intermediate stages of solving the puzzle.)
+
+\dt \e{Jumble tiles}: \q{J} key
+
+\dd This key turns all tiles that are not locked to random
+orientations.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{net-params} \I{parameters, for Net}Net parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in tiles.
+
+\dt \e{Walls wrap around}
+
+\dd If checked, flow can pass from the left edge to the right edge,
+and from top to bottom, and vice versa.
+
+\dt \e{Barrier probability}
+
+\dd A number between 0.0 and 1.0 controlling whether an immovable
+barrier is placed between two tiles to prevent flow between them (a
+higher number gives more barriers). Since barriers are immovable, they
+act as constraints on the solution (i.e., hints).
+
+\lcont{
+
+The grid generation in Net has been carefully arranged so that the
+barriers are independent of the rest of the grid. This means that if
+you note down the random seed used to generate the current puzzle
+(see \k{common-id}), change the \e{Barrier probability} parameter,
+and then re-enter the same random seed, you should see exactly the
+same starting grid, with the only change being the number of
+barriers. So if you're stuck on a particular grid and need a hint,
+you could start up another instance of Net, set up the same
+parameters but a higher barrier probability, and enter the game seed
+from the original Net window.
+
+}
+
+\dt \e{Ensure unique solution}
+
+\dd Normally, Net will make sure that the puzzles it presents have
+only one solution. Puzzles with ambiguous sections can be more
+difficult and more subtle, so if you like you can turn off this
+feature and risk having ambiguous puzzles. (Also, finding \e{all}
+the possible solutions can be an additional challenge for an
+advanced player.)
+
+
+\C{cube} \i{Cube}
+
+\cfg{winhelp-topic}{games.cube}
+
+This is another one I originally saw as a web game. This one was a
+Java game \k{cube-java-game}, by Paul Scott. You have a grid of 16
+squares, six of which are blue; on one square rests a cube. Your move
+is to use the arrow keys to roll the cube through 90 degrees so that
+it moves to an adjacent square. If you roll the cube on to a blue
+square, the blue square is picked up on one face of the cube; if you
+roll a blue face of the cube on to a non-blue square, the blueness is
+put down again. (In general, whenever you roll the cube, the two faces
+that come into contact swap colours.) Your job is to get all six blue
+squares on to the six faces of the cube at the same time. Count your
+moves and try to do it in as few as possible. 
+
+Unlike the original Java game, my version has an additional feature:
+once you've mastered the game with a cube rolling on a square grid,
+you can change to a triangular grid and roll any of a tetrahedron, an
+octahedron or an icosahedron. 
+
+\B{cube-java-game} \W{http://www3.sympatico.ca/paulscott/cube/cube.htm}\cw{http://www3.sympatico.ca/paulscott/cube/cube.htm}
+
+\H{cube-controls} \i{Cube controls}
+
+\IM{Cube controls} controls, for Cube
+\IM{Cube controls} keys, for Cube
+\IM{Cube controls} shortcuts (keyboard), for Cube
+
+This game can be played with either the keyboard or the mouse.
+
+Left-clicking anywhere on the window will move the cube (or other
+solid) towards the mouse pointer.
+
+The arrow keys can also used to roll the cube on its square grid in
+the four cardinal directions.
+On the triangular grids, the mapping of arrow keys to directions is
+more approximate. Vertical movement is disallowed where it doesn't
+make sense. The four keys surrounding the arrow keys on the numeric
+keypad (\q{7}, \q{9}, \q{1}, \q{3}) can be used for diagonal movement.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{cube-params} \I{parameters, for Cube}Cube parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Type of solid}
+
+\dd Selects the solid to roll (and hence the shape of the grid):
+tetrahedron, cube, octahedron, or icosahedron.
+
+\dt \e{Width / top}, \e{Height / bottom}
+
+\dd On a square grid, horizontal and vertical dimensions. On a
+triangular grid, the number of triangles on the top and bottom rows
+respectively.
+
+
+\C{fifteen} \i{Fifteen}
+
+\cfg{winhelp-topic}{games.fifteen}
+
+The old ones are the best: this is the good old \q{\i{15-puzzle}}
+with sliding tiles. You have a 4\by\.4 square grid; 15 squares
+contain numbered tiles, and the sixteenth is empty. Your move is to
+choose a tile next to the empty space, and slide it into the space.
+The aim is to end up with the tiles in numerical order, with the
+space in the bottom right (so that the top row reads 1,2,3,4 and the
+bottom row reads 13,14,15,\e{space}).
+
+\H{fifteen-controls} \i{Fifteen controls}
+
+\IM{Fifteen controls} controls, for Fifteen
+\IM{Fifteen controls} keys, for Fifteen
+\IM{Fifteen controls} shortcuts (keyboard), for Fifteen
+
+This game can be controlled with the mouse or the keyboard.
+
+A left-click with the mouse in the row or column containing the empty
+space will move as many tiles as necessary to move the space to the
+mouse pointer.
+
+The arrow keys will move a tile adjacent to the space in the direction
+indicated (moving the space in the \e{opposite} direction).
+
+Pressing \q{h} will make a suggested move.  Pressing \q{h} enough
+times will solve the game, but it may scramble your progress while
+doing so.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{fifteen-params} \I{parameters, for Fifteen}Fifteen parameters
+
+The only options available from the \q{Custom...} option on the \q{Type}
+menu are \e{Width} and \e{Height}, which are self-explanatory. (Once
+you've changed these, it's not a \q{15-puzzle} any more, of course!)
+
+
+\C{sixteen} \i{Sixteen}
+
+\cfg{winhelp-topic}{games.sixteen}
+
+Another sliding tile puzzle, visually similar to Fifteen (see
+\k{fifteen}) but with a different type of move. This time, there is no
+hole: all 16 squares on the grid contain numbered squares. Your move
+is to shift an entire row left or right, or shift an entire column up
+or down; every time you do that, the tile you shift off the grid
+re-appears at the other end of the same row, in the space you just
+vacated. To win, arrange the tiles into numerical order (1,2,3,4 on
+the top row, 13,14,15,16 on the bottom). When you've done that, try
+playing on different sizes of grid. 
+
+I \e{might} have invented this game myself, though only by accident if
+so (and I'm sure other people have independently invented it). I
+thought I was imitating a screensaver I'd seen, but I have a feeling
+that the screensaver might actually have been a Fifteen-type puzzle
+rather than this slightly different kind. So this might be the one
+thing in my puzzle collection which represents creativity on my part
+rather than just engineering.
+
+\H{sixteen-controls} \I{controls, for Sixteen}Sixteen controls
+
+Left-clicking on an arrow will move the appropriate row or column in
+the direction indicated.  Right-clicking will move it in the opposite
+direction.
+
+Alternatively, use the cursor keys to move the position indicator
+around the edge of the grid, and use the return key to move the
+row/column in the direction indicated. 
+
+You can also move the tiles directly.  Move the cursor onto a tile,
+hold Control and press an arrow key to move the tile under the
+cursor and move the cursor along with the tile.  Or, hold Shift to
+move only the tile.  Pressing Enter simulates holding down Control
+(press Enter again to release), while pressing Space simulates
+holding down shift.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{sixteen-params} \I{parameters, for Sixteen}Sixteen parameters
+
+The parameters available from the \q{Custom...} option on the
+\q{Type} menu are:
+
+\b \e{Width} and \e{Height}, which are self-explanatory.
+
+\b You can ask for a limited shuffling operation to be performed on
+the grid. By default, Sixteen will shuffle the grid in such a way
+that any arrangement is about as probable as any other. You can
+override this by requesting a precise number of shuffling moves to
+be performed. Typically your aim is then to determine the precise
+set of shuffling moves and invert them exactly, so that you answer
+(say) a four-move shuffle with a four-move solution. Note that the
+more moves you ask for, the more likely it is that solutions shorter
+than the target length will turn out to be possible.
+
+
+\C{twiddle} \i{Twiddle}
+
+\cfg{winhelp-topic}{games.twiddle}
+
+Twiddle is a tile-rearrangement puzzle, visually similar to Sixteen
+(see \k{sixteen}): you are given a grid of square tiles, each
+containing a number, and your aim is to arrange the numbers into
+ascending order.
+
+In basic Twiddle, your move is to rotate a square group of four
+tiles about their common centre. (Orientation is not significant in
+the basic puzzle, although you can select it.) On more advanced
+settings, you can rotate a larger square group of tiles.
+
+I first saw this type of puzzle in the GameCube game \q{Metroid
+Prime 2}. In the Main Gyro Chamber in that game, there is a puzzle
+you solve to unlock a door, which is a special case of Twiddle. I
+developed this game as a generalisation of that puzzle.
+
+\H{twiddle-controls} \I{controls, for Twiddle}Twiddle controls
+
+To play Twiddle, click the mouse in the centre of the square group
+you wish to rotate. In the basic mode, you rotate a 2\by\.2 square,
+which means you have to click at a corner point where four tiles
+meet.
+
+In more advanced modes you might be rotating 3\by\.3 or even more at
+a time; if the size of the square is odd then you simply click in
+the centre tile of the square you want to rotate.
+
+Clicking with the left mouse button rotates the group anticlockwise.
+Clicking with the right button rotates it clockwise.
+
+You can also move an outline square around the grid with the cursor
+keys; the square is the size above (2\by\.2 by default, or larger).
+Pressing the return key or space bar will rotate the current square
+anticlockwise or clockwise respectively.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{twiddle-parameters} \I{parameters, for Twiddle}Twiddle parameters
+
+Twiddle provides several configuration options via the \q{Custom}
+option on the \q{Type} menu:
+
+\b You can configure the width and height of the puzzle grid.
+
+\b You can configure the size of square block that rotates at a time.
+
+\b You can ask for every square in the grid to be distinguishable
+(the default), or you can ask for a simplified puzzle in which there
+are groups of identical numbers. In the simplified puzzle your aim
+is just to arrange all the 1s into the first row, all the 2s into
+the second row, and so on.
+
+\b You can configure whether the orientation of tiles matters. If
+you ask for an orientable puzzle, each tile will have a triangle
+drawn in it. All the triangles must be pointing upwards to complete
+the puzzle.
+
+\b You can ask for a limited shuffling operation to be performed on
+the grid. By default, Twiddle will shuffle the grid so much that any
+arrangement is about as probable as any other. You can override this
+by requesting a precise number of shuffling moves to be performed.
+Typically your aim is then to determine the precise set of shuffling
+moves and invert them exactly, so that you answer (say) a four-move
+shuffle with a four-move solution. Note that the more moves you ask
+for, the more likely it is that solutions shorter than the target
+length will turn out to be possible.
+
+
+\C{rect} \i{Rectangles}
+
+\cfg{winhelp-topic}{games.rectangles}
+
+You have a grid of squares, with numbers written in some (but not all)
+of the squares. Your task is to subdivide the grid into rectangles of
+various sizes, such that (a) every rectangle contains exactly one
+numbered square, and (b) the area of each rectangle is equal to the
+number written in its numbered square.
+
+Credit for this game goes to the Japanese puzzle magazine \i{Nikoli}
+\k{nikoli-rect}; I've also seen a Palm implementation at \i{Puzzle
+Palace} \k{puzzle-palace-rect}. Unlike Puzzle Palace's
+implementation, my version automatically generates random grids of
+any size you like. The quality of puzzle design is therefore not
+quite as good as hand-crafted puzzles would be, but on the plus side
+you get an inexhaustible supply of puzzles tailored to your own
+specification.
+
+\B{nikoli-rect} \W{http://www.nikoli.co.jp/en/puzzles/shikaku.html}\cw{http://www.nikoli.co.jp/en/puzzles/shikaku.html}
+(beware of Flash)
+
+\B{puzzle-palace-rect} \W{https://web.archive.org/web/20041024001459/http://www.puzzle.gr.jp/puzzle/sikaku/palm/index.html.en}\cw{https://web.archive.org/web/20041024001459/http://www.puzzle.gr.jp/puzzle/sikaku/palm/index.html.en}
+
+\H{rectangles-controls} \I{controls, for Rectangles}Rectangles controls
+
+This game is played with the mouse or cursor keys.
+
+Left-click any edge to toggle it on or off, or left-click and drag to draw
+an entire rectangle (or line) on the grid in one go (removing any existing
+edges within that rectangle). Right-clicking and dragging will allow you
+to erase the contents of a rectangle without affecting its edges. 
+
+Alternatively, use the cursor keys to move the position indicator
+around the board. Pressing the return key then allows you to use the
+cursor keys to drag a rectangle out from that position, and pressing
+the return key again completes the rectangle. Using the space bar
+instead of the return key allows you to erase the contents of a
+rectangle without affecting its edges, as above. Pressing escape
+cancels a drag.
+
+When a rectangle of the correct size is completed, it will be shaded.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{rectangles-params} \I{parameters, for Rectangles}Rectangles parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid, in squares.
+
+\dt \e{Expansion factor}
+
+\dd This is a mechanism for changing the type of grids generated by
+the program. Some people prefer a grid containing a few large
+rectangles to one containing many small ones. So you can ask
+Rectangles to essentially generate a \e{smaller} grid than the size
+you specified, and then to expand it by adding rows and columns.
+
+\lcont{
+
+The default expansion factor of zero means that Rectangles will
+simply generate a grid of the size you ask for, and do nothing
+further. If you set an expansion factor of (say) 0.5, it means that
+each dimension of the grid will be expanded to half again as big
+after generation. In other words, the initial grid will be 2/3 the
+size in each dimension, and will be expanded to its full size
+without adding any more rectangles.
+
+Setting an expansion factor of around 0.5 tends to make the game
+more difficult, and also (in my experience) rewards a less deductive
+and more intuitive playing style. If you set it \e{too} high,
+though, the game simply cannot generate more than a few rectangles
+to cover the entire grid, and the game becomes trivial.
+
+}
+
+\dt \e{Ensure unique solution}
+
+\dd Normally, Rectangles will make sure that the puzzles it presents
+have only one solution. Puzzles with ambiguous sections can be more
+difficult and more subtle, so if you like you can turn off this
+feature and risk having ambiguous puzzles. Also, finding \e{all} the
+possible solutions can be an additional challenge for an advanced
+player. Turning off this option can also speed up puzzle generation.
+
+
+\C{netslide} \i{Netslide}
+
+\cfg{winhelp-topic}{games.netslide}
+
+This game combines the grid generation of Net (see \k{net}) with the
+movement of Sixteen (see \k{sixteen}): you have a Net grid, but
+instead of rotating tiles back into place you have to slide them
+into place by moving a whole row at a time. 
+
+As in Sixteen, \I{controls, for Netslide}control is with the mouse or
+cursor keys. See \k{sixteen-controls}.
+
+\I{parameters, for Netslide}The available game parameters have similar
+meanings to those in Net (see \k{net-params}) and Sixteen (see
+\k{sixteen-params}).
+
+Netslide was contributed to this collection by Richard Boulton.
+
+
+\C{pattern} \i{Pattern}
+
+\cfg{winhelp-topic}{games.pattern}
+
+You have a grid of squares, which must all be filled in either black
+or white. Beside each row of the grid are listed the lengths of the
+runs of black squares on that row; above each column are listed the
+lengths of the runs of black squares in that column. Your aim is to
+fill in the entire grid black or white.
+
+I first saw this puzzle form around 1995, under the name
+\q{\i{nonograms}}. I've seen it in various places since then, under
+different names.
+
+Normally, puzzles of this type turn out to be a meaningful picture
+of something once you've solved them. However, since this version
+generates the puzzles automatically, they will just look like random
+groupings of squares. (One user has suggested that this is actually
+a \e{good} thing, since it prevents you from guessing the colour of
+squares based on the picture, and forces you to use logic instead.)
+The advantage, though, is that you never run out of them.
+
+\H{pattern-controls} \I{controls, for Pattern}Pattern controls
+
+This game is played with the mouse.
+
+Left-click in a square to colour it black. Right-click to colour it
+white. If you make a mistake, you can middle-click, or hold down
+Shift while clicking with any button, to colour the square in the
+default grey (meaning \q{undecided}) again.
+
+You can click and drag with the left or right mouse button to colour
+a vertical or horizontal line of squares black or white at a time
+(respectively). If you click and drag with the middle button, or
+with Shift held down, you can colour a whole rectangle of squares
+grey.
+
+You can also move around the grid with the cursor keys. Pressing the
+return key will cycle the current cell through empty, then black, then
+white, then empty, and the space bar does the same cycle in reverse.
+
+Moving the cursor while holding Control will colour the moved-over
+squares black.  Holding Shift will colour the moved-over squares
+white, and holding both will colour them grey.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{pattern-parameters} \I{parameters, for Pattern}Pattern parameters
+
+The only options available from the \q{Custom...} option on the \q{Type}
+menu are \e{Width} and \e{Height}, which are self-explanatory.
+
+
+\C{solo} \i{Solo}
+
+\cfg{winhelp-topic}{games.solo}
+
+You have a square grid, which is divided into as many equally sized
+sub-blocks as the grid has rows. Each square must be filled in with
+a digit from 1 to the size of the grid, in such a way that
+
+\b every row contains only one occurrence of each digit
+
+\b every column contains only one occurrence of each digit
+
+\b every block contains only one occurrence of each digit.
+
+\b (optionally, by default off) each of the square's two main
+diagonals contains only one occurrence of each digit.
+
+You are given some of the numbers as clues; your aim is to place the
+rest of the numbers correctly.
+
+Under the default settings, the sub-blocks are square or
+rectangular. The default puzzle size is 3\by\.3 (a 9\by\.9 actual
+grid, divided into nine 3\by\.3 blocks). You can also select sizes
+with rectangular blocks instead of square ones, such as 2\by\.3 (a
+6\by\.6 grid divided into six 3\by\.2 blocks). Alternatively, you
+can select \q{jigsaw} mode, in which the sub-blocks are arbitrary
+shapes which differ between individual puzzles.
+
+Another available mode is \q{killer}. In this mode, clues are not
+given in the form of filled-in squares; instead, the grid is divided
+into \q{cages} by coloured lines, and for each cage the game tells
+you what the sum of all the digits in that cage should be. Also, no
+digit may appear more than once within a cage, even if the cage
+crosses the boundaries of existing regions.
+
+If you select a puzzle size which requires more than 9 digits, the
+additional digits will be letters of the alphabet. For example, if
+you select 3\by\.4 then the digits which go in your grid will be 1
+to 9, plus \cq{a}, \cq{b} and \cq{c}. This cannot be selected for
+killer puzzles.
+
+I first saw this puzzle in \i{Nikoli} \k{nikoli-solo}, although it's
+also been popularised by various newspapers under the name
+\q{Sudoku} or \q{Su Doku}.  Howard Garns is considered the inventor
+of the modern form of the puzzle, and it was first published in
+\e{Dell Pencil Puzzles and Word Games}.  A more elaborate treatment
+of the history of the puzzle can be found on Wikipedia
+\k{wikipedia-solo}.
+
+\B{nikoli-solo} \W{http://www.nikoli.co.jp/en/puzzles/sudoku.html}\cw{http://www.nikoli.co.jp/en/puzzles/sudoku.html}
+(beware of Flash)
+
+\B{wikipedia-solo} \W{http://en.wikipedia.org/wiki/Sudoku}\cw{http://en.wikipedia.org/wiki/Sudoku}
+
+\H{solo-controls} \I{controls, for Solo}Solo controls
+
+To play Solo, simply click the mouse in any empty square and then
+type a digit or letter on the keyboard to fill that square. If you
+make a mistake, click the mouse in the incorrect square and press
+Space to clear it again (or use the Undo feature).
+
+If you \e{right}-click in a square and then type a number, that
+number will be entered in the square as a \q{pencil mark}. You can
+have pencil marks for multiple numbers in the same square. Squares
+containing filled-in numbers cannot also contain pencil marks.
+
+The game pays no attention to pencil marks, so exactly what you use
+them for is up to you: you can use them as reminders that a
+particular square needs to be re-examined once you know more about a
+particular number, or you can use them as lists of the possible
+numbers in a given square, or anything else you feel like.
+
+To erase a single pencil mark, right-click in the square and type
+the same number again.
+
+All pencil marks in a square are erased when you left-click and type
+a number, or when you left-click and press space. Right-clicking and
+pressing space will also erase pencil marks.
+
+Alternatively, use the cursor keys to move the mark around the grid.
+Pressing the return key toggles the mark (from a normal mark to a
+pencil mark), and typing a number in is entered in the square in the
+appropriate way; typing in a 0 or using the space bar will clear a
+filled square. 
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{solo-parameters} \I{parameters, for Solo}Solo parameters
+
+Solo allows you to configure two separate dimensions of the puzzle
+grid on the \q{Type} menu: the number of columns, and the number of
+rows, into which the main grid is divided. (The size of a block is
+the inverse of this: for example, if you select 2 columns and 3 rows,
+each actual block will have 3 columns and 2 rows.)
+
+If you tick the \q{X} checkbox, Solo will apply the optional extra
+constraint that the two main diagonals of the grid also contain one
+of every digit. (This is sometimes known as \q{Sudoku-X} in
+newspapers.) In this mode, the squares on the two main diagonals
+will be shaded slightly so that you know it's enabled.
+
+If you tick the \q{Jigsaw} checkbox, Solo will generate randomly
+shaped sub-blocks. In this mode, the actual grid size will be taken
+to be the product of the numbers entered in the \q{Columns} and
+\q{Rows} boxes. There is no reason why you have to enter a number
+greater than 1 in both boxes; Jigsaw mode has no constraint on the
+grid size, and it can even be a prime number if you feel like it.
+
+If you tick the \q{Killer} checkbox, Solo will generate a set of
+of cages, which are randomly shaped and drawn in an outline of a
+different colour.  Each of these regions contains a smaller clue
+which shows the digit sum of all the squares in this region.
+
+You can also configure the type of symmetry shown in the generated
+puzzles. More symmetry makes the puzzles look prettier but may also
+make them easier, since the symmetry constraints can force more
+clues than necessary to be present. Completely asymmetric puzzles
+have the freedom to contain as few clues as possible.
+
+Finally, you can configure the difficulty of the generated puzzles.
+Difficulty levels are judged by the complexity of the techniques of
+deduction required to solve the puzzle: each level requires a mode
+of reasoning which was not necessary in the previous one. In
+particular, on difficulty levels \q{Trivial} and \q{Basic} there
+will be a square you can fill in with a single number at all times,
+whereas at \q{Intermediate} level and beyond you will have to make
+partial deductions about the \e{set} of squares a number could be in
+(or the set of numbers that could be in a square).
+\#{Advanced, Extreme?}
+At \q{Unreasonable} level, even this is not enough, and you will
+eventually have to make a guess, and then backtrack if it turns out
+to be wrong.
+
+Generating difficult puzzles is itself difficult: if you select one
+of the higher difficulty levels, Solo may have to make many attempts
+at generating a puzzle before it finds one hard enough for you. Be
+prepared to wait, especially if you have also configured a large
+puzzle size.
+
+
+\C{mines} \i{Mines}
+
+\cfg{winhelp-topic}{games.mines}
+
+You have a grid of covered squares, some of which contain mines, but
+you don't know which. Your job is to uncover every square which does
+\e{not} contain a mine. If you uncover a square containing a mine,
+you lose. If you uncover a square which does not contain a mine, you
+are told how many mines are contained within the eight surrounding
+squares.
+
+This game needs no introduction; popularised by Windows, it is
+perhaps the single best known desktop puzzle game in existence.
+
+This version of it has an unusual property. By default, it will
+generate its mine positions in such a way as to ensure that you
+never need to \e{guess} where a mine is: you will always be able to
+deduce it somehow. So you will never, as can happen in other
+versions, get to the last four squares and discover that there are
+two mines left but you have no way of knowing for sure where they
+are.
+
+\H{mines-controls} \I{controls, for Mines}Mines controls
+
+This game is played with the mouse.
+
+If you left-click in a covered square, it will be uncovered.
+
+If you right-click in a covered square, it will place a flag which
+indicates that the square is believed to be a mine. Left-clicking in
+a marked square will not uncover it, for safety. You can right-click
+again to remove a mark placed in error.
+
+If you left-click in an \e{uncovered} square, it will \q{clear
+around} the square. This means: if the square has exactly as many
+flags surrounding it as it should have mines, then all the covered
+squares next to it which are \e{not} flagged will be uncovered. So
+once you think you know the location of all the mines around a
+square, you can use this function as a shortcut to avoid having to
+click on each of the remaining squares one by one.
+
+If you uncover a square which has \e{no} mines in the surrounding
+eight squares, then it is obviously safe to uncover those squares in
+turn, and so on if any of them also has no surrounding mines. This
+will be done for you automatically; so sometimes when you uncover a
+square, a whole new area will open up to be explored.
+
+You can also use the cursor keys to move around the minefield.
+Pressing the return key in a covered square uncovers it, and in an
+uncovered square will clear around it (so it acts as the left button),
+pressing the space bar in a covered square will place a flag
+(similarly, it acts as the right button).
+
+All the actions described in \k{common-actions} are also available.
+
+Even Undo is available, although you might consider it cheating to
+use it. If you step on a mine, the program will only reveal the mine
+in question (unlike most other implementations, which reveal all of
+them). You can then Undo your fatal move and continue playing if you
+like. The program will track the number of times you died (and Undo
+will not reduce that counter), so when you get to the end of the
+game you know whether or not you did it without making any errors.
+
+(If you really want to know the full layout of the grid, which other
+implementations will show you after you die, you can always use the
+Solve menu option.)
+
+\H{mines-parameters} \I{parameters, for Mines}Mines parameters
+
+The options available from the \q{Custom...} option on the \q{Type}
+menu are:
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Mines}
+
+\dd Number of mines in the grid. You can enter this as an absolute
+mine count, or alternatively you can put a \cw{%} sign on the end in
+which case the game will arrange for that proportion of the squares
+in the grid to be mines.
+
+\lcont{
+
+Beware of setting the mine count too high. At very high densities,
+the program may spend forever searching for a solvable grid.
+
+}
+
+\dt \e{Ensure solubility}
+
+\dd When this option is enabled (as it is by default), Mines will
+ensure that the entire grid can be fully deduced starting from the
+initial open space. If you prefer the riskier grids generated by
+other implementations, you can switch off this option.
+
+
+\C{samegame} \i{Same Game}
+
+\cfg{winhelp-topic}{games.samegame}
+
+You have a grid of coloured squares, which you have to clear by 
+highlighting contiguous regions of more than one coloured square;
+the larger the region you highlight, the more points you get (and
+the faster you clear the arena).
+
+If you clear the grid you win. If you end up with nothing but 
+single squares (i.e., there are no more clickable regions left) you
+lose.
+
+Removing a region causes the rest of the grid to shuffle up:
+blocks that are suspended will fall down (first), and then empty
+columns are filled from the right. 
+
+Same Game was contributed to this collection by James Harvey.
+
+\H{samegame-controls} \i{Same Game controls}
+
+\IM{Same Game controls} controls, for Same Game
+\IM{Same Game controls} keys, for Same Game
+\IM{Same Game controls} shortcuts (keyboard), for Same Game
+
+This game can be played with either the keyboard or the mouse.
+
+If you left-click an unselected region, it becomes selected (possibly
+clearing the current selection). 
+
+If you left-click the selected region, it will be removed (and the
+rest of the grid shuffled immediately).
+
+If you right-click the selected region, it will be unselected. 
+
+The cursor keys move a cursor around the grid. Pressing the Space or
+Enter keys while the cursor is in an unselected region selects it;
+pressing Space or Enter again removes it as above.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{samegame-parameters} \I{parameters, for Same Game}Same Game parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{No. of colours}
+
+\dd Number of different colours used to fill the grid; the more colours,
+the fewer large regions of colour and thus the more difficult it is to
+successfully clear the grid.
+
+\dt \e{Scoring system}
+
+\dd Controls the precise mechanism used for scoring. With the default
+system, \q{(n-2)^2}, only regions of three squares or more will score
+any points at all. With the alternative \q{(n-1)^2} system, regions of
+two squares score a point each, and larger regions score relatively
+more points.
+
+\dt \e{Ensure solubility}
+
+\dd If this option is ticked (the default state), generated grids
+will be guaranteed to have at least one solution.
+
+\lcont{
+
+If you turn it off, the game generator will not try to guarantee
+soluble grids; it will, however, still ensure that there are at
+least 2 squares of each colour on the grid at the start (since a
+grid with exactly one square of a given colour is \e{definitely}
+insoluble). Grids generated with this option disabled may contain
+more large areas of contiguous colour, leading to opportunities for
+higher scores; they can also take less time to generate.
+
+}
+
+
+\C{flip} \i{Flip}
+
+\cfg{winhelp-topic}{games.flip}
+
+You have a grid of squares, some light and some dark. Your aim is to
+light all the squares up at the same time. You can choose any square
+and flip its state from light to dark or dark to light, but when you
+do so, other squares around it change state as well.
+
+Each square contains a small diagram showing which other squares
+change when you flip it.
+
+\H{flip-controls} \i{Flip controls}
+
+\IM{Flip controls} controls, for Flip
+\IM{Flip controls} keys, for Flip
+\IM{Flip controls} shortcuts (keyboard), for Flip
+
+This game can be played with either the keyboard or the mouse.
+
+Left-click in a square to flip it and its associated squares, or
+use the cursor keys to choose a square and the space bar or Enter
+key to flip.
+
+If you use the \q{Solve} function on this game, it will mark some of
+the squares in red. If you click once in every square with a red
+mark, the game should be solved. (If you click in a square
+\e{without} a red mark, a red mark will appear in it to indicate
+that you will need to reverse that operation to reach the solution.)
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{flip-parameters} \I{parameters, for flip}Flip parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Shape type}
+
+\dd This control determines the shape of the region which is flipped
+by clicking in any given square. The default setting, \q{Crosses},
+causes every square to flip itself and its four immediate neighbours
+(or three or two if it's at an edge or corner). The other setting,
+\q{Random}, causes a random shape to be chosen for every square, so
+the game is different every time.
+
+
+\C{guess} \i{Guess}
+
+\cfg{winhelp-topic}{games.guess}
+
+You have a set of coloured pegs, and have to reproduce a
+predetermined sequence of them (chosen by the computer) within a
+certain number of guesses. 
+
+Each guess gets marked with the number of correctly-coloured pegs
+in the correct places (in black), and also the number of
+correctly-coloured pegs in the wrong places (in white). 
+
+This game is also known (and marketed, by Hasbro, mainly) as
+a board game \q{\i{Mastermind}}, with 6 colours, 4 pegs per row,
+and 10 guesses. However, this version allows custom settings of number
+of colours (up to 10), number of pegs per row, and number of guesses. 
+
+Guess was contributed to this collection by James Harvey.
+
+\H{guess-controls} \i{Guess controls}
+
+\IM{Guess controls} controls, for Guess
+\IM{Guess controls} keys, for Guess
+\IM{Guess controls} shortcuts (keyboard), for Guess
+
+This game can be played with either the keyboard or the mouse.
+
+With the mouse, drag a coloured peg from the tray on the left-hand
+side to its required position in the current guess; pegs may also be
+dragged from current and past guesses to copy them elsewhere. To
+remove a peg, drag it off its current position to somewhere invalid.
+
+Right-clicking in the current guess adds a \q{hold} marker; pegs
+that have hold markers will be automatically added to the next guess
+after marking.
+
+Alternatively, with the keyboard, the up and down cursor keys can be
+used to select a peg colour, the left and right keys to select a
+peg position, and the space bar or Enter key to place a peg of the
+selected colour in the chosen position. \q{D} or Backspace removes a
+peg, and Space adds a hold marker.
+
+Pressing \q{h} or \q{?} will fill the current guess with a suggested
+guess.  Using this is not recommended for 10 or more pegs as it is
+slow.
+
+When the guess is complete, the smaller feedback pegs will be highlighted;
+clicking on these (or moving the peg cursor to them with the arrow keys
+and pressing the space bar or Enter key) will mark the current guess,
+copy any held pegs to the next guess, and move the \q{current guess}
+marker.
+
+If you correctly position all the pegs the solution will be displayed
+below; if you run out of guesses (or select \q{Solve...}) the solution
+will also be revealed.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{guess-parameters} \I{parameters, for Guess}Guess parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu. The default game matches the parameters for the 
+board game \q{Mastermind}. 
+
+\dt \e{Colours}
+
+\dd Number of colours the solution is chosen from; from 2 to 10
+(more is harder).
+
+\dt \e{Pegs per guess}
+
+\dd Number of pegs per guess (more is harder).
+
+\dt \e{Guesses}
+
+\dd Number of guesses you have to find the solution in (fewer is harder).
+
+\dt \e{Allow blanks}
+
+\dd Allows blank pegs to be given as part of a guess (makes it easier, because
+you know that those will never be counted as part of the solution). This
+is turned off by default. 
+
+\lcont{
+
+Note that this doesn't allow blank pegs in the solution; if you really wanted
+that, use one extra colour.
+
+}
+
+\dt \e{Allow duplicates}
+
+\dd Allows the solution (and the guesses) to contain colours more than once;
+this increases the search space (making things harder), and is turned on by
+default.
+
+
+\C{pegs} \i{Pegs}
+
+\cfg{winhelp-topic}{games.pegs}
+
+A number of pegs are placed in holes on a board. You can remove a
+peg by jumping an adjacent peg over it (horizontally or vertically)
+to a vacant hole on the other side. Your aim is to remove all but one
+of the pegs initially present.
+
+This game, best known as \I{Solitaire, Peg}\q{Peg Solitaire}, is
+possibly one of the oldest puzzle games still commonly known.
+
+\H{pegs-controls} \i{Pegs controls}
+
+\IM{Pegs controls} controls, for Pegs
+
+To move a peg, drag it with the mouse from its current position to
+its final position. If the final position is exactly two holes away
+from the initial position, is currently unoccupied by a peg, and
+there is a peg in the intervening square, the move will be permitted
+and the intervening peg will be removed.
+
+Vacant spaces which you can move a peg into are marked with holes. A
+space with no peg and no hole is not available for moving at all: it
+is an obstacle which you must work around.
+
+You can also use the cursor keys to move a position indicator around
+the board. Pressing the return key while over a peg, followed by a
+cursor key, will jump the peg in that direction (if that is a legal
+move).
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{pegs-parameters} \I{parameters, for Pegs}Pegs parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in holes.
+
+\dt \e{Board type}
+
+\dd Controls whether you are given a board of a standard shape or a
+randomly generated shape. The two standard shapes currently
+supported are \q{Cross} and \q{Octagon} (also commonly known as the
+English and European traditional board layouts respectively).
+Selecting \q{Random} will give you a different board shape every
+time (but always one that is known to have a solution).
+
+
+\C{dominosa} \i{Dominosa}
+
+\cfg{winhelp-topic}{games.dominosa}
+
+A normal set of dominoes \dash that is, one instance of every
+(unordered) pair of numbers from 0 to 6 \dash has been arranged
+irregularly into a rectangle; then the number in each square has
+been written down and the dominoes themselves removed. Your task is
+to reconstruct the pattern by arranging the set of dominoes to match
+the provided array of numbers.
+
+This puzzle is widely credited to O. S. Adler, and takes part of its
+name from those initials.
+
+\H{dominosa-controls} \i{Dominosa controls}
+
+\IM{Dominosa controls} controls, for Dominosa
+
+Left-clicking between any two adjacent numbers places a domino
+covering them, or removes one if it is already present. Trying to
+place a domino which overlaps existing dominoes will remove the ones
+it overlaps.
+
+Right-clicking between two adjacent numbers draws a line between
+them, which you can use to remind yourself that you know those two
+numbers are \e{not} covered by a single domino. Right-clicking again
+removes the line.
+
+You can also use the cursor keys to move a cursor around the grid.
+When the cursor is half way between two adjacent numbers, pressing
+the return key will place a domino covering those numbers, or
+pressing the space bar will lay a line between the two squares.
+Repeating either action removes the domino or line.
+
+Pressing a number key will highlight all occurrences of that
+number. Pressing that number again will clear the highlighting. Up to two
+different numbers can be highlighted at any given time.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{dominosa-parameters} \I{parameters, for Dominosa}Dominosa parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Maximum number on dominoes}
+
+\dd Controls the size of the puzzle, by controlling the size of the
+set of dominoes used to make it. Dominoes with numbers going up to N
+will give rise to an (N+2) \by (N+1) rectangle; so, in particular,
+the default value of 6 gives an 8\by\.7 grid.
+
+\dt \e{Ensure unique solution}
+
+\dd Normally, Dominosa will make sure that the puzzles it presents
+have only one solution. Puzzles with ambiguous sections can be more
+difficult and sometimes more subtle, so if you like you can turn off
+this feature. Also, finding \e{all} the possible solutions can be an
+additional challenge for an advanced player. Turning off this option
+can also speed up puzzle generation.
+
+
+\C{untangle} \i{Untangle}
+
+\cfg{winhelp-topic}{games.untangle}
+
+You are given a number of points, some of which have lines drawn
+between them. You can move the points about arbitrarily; your aim is
+to position the points so that no line crosses another.
+
+I originally saw this in the form of a Flash game called \i{Planarity}
+\k{Planarity}, written by John Tantalo.
+
+\B{Planarity} \W{http://planarity.net}\cw{http://planarity.net}
+
+\H{untangle-controls} \i{Untangle controls}
+
+\IM{Untangle controls} controls, for Untangle
+
+To move a point, click on it with the left mouse button and drag it
+into a new position.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{untangle-parameters} \I{parameters, for Untangle}Untangle parameters
+
+There is only one parameter available from the \q{Custom...} option
+on the \q{Type} menu:
+
+\dt \e{Number of points}
+
+\dd Controls the size of the puzzle, by specifying the number of
+points in the generated graph.
+
+
+\C{blackbox} \i{Black Box}
+
+\cfg{winhelp-topic}{games.blackbox}
+
+A number of balls are hidden in a rectangular arena. You have to
+deduce the positions of the balls by firing lasers positioned at
+the edges of the arena and observing how their beams are deflected. 
+
+Beams will travel straight from their origin until they hit the
+opposite side of the arena (at which point they emerge), unless
+affected by balls in one of the following ways:
+
+\b A beam that hits a ball head-on is absorbed and will never
+   re-emerge. This includes beams that meet a ball on the first rank
+   of the arena.
+
+\b A beam with a ball in its front-left square and no ball ahead of it
+   gets deflected 90 degrees to the right.
+
+\b A beam with a ball in its front-right square and no ball ahead of
+   it gets similarly deflected to the left.
+
+\b A beam that would re-emerge from its entry location is considered to be
+   \q{reflected}. 
+
+\b A beam which would get deflected before entering the arena by a
+   ball to the front-left or front-right of its entry point is also
+   considered to be \q{reflected}.
+
+Beams that are reflected appear as a \q{R}; beams that hit balls
+head-on appear as \q{H}. Otherwise, a number appears at the firing
+point and the location where the beam emerges (this number is unique
+to that shot).
+
+You can place guesses as to the location of the balls, based on the
+entry and exit patterns of the beams; once you have placed enough
+balls a button appears enabling you to have your guesses checked. 
+
+Here is a diagram showing how the positions of balls can create each
+of the beam behaviours shown above:
+
+\c  1RHR---- 
+\c |..O.O...|
+\c 2........3
+\c |........|
+\c |........|
+\c 3........|
+\c |......O.|
+\c H........|
+\c |.....O..|
+\c  12-RR---
+
+As shown, it is possible for a beam to receive multiple reflections
+before re-emerging (see turn 3). Similarly, a beam may be reflected
+(possibly more than once) before receiving a hit (the \q{H} on the
+left side of the example).
+
+Note that any layout with more than 4 balls may have a non-unique
+solution.  The following diagram illustrates this; if you know the
+board contains 5 balls, it is impossible to determine where the fifth
+ball is (possible positions marked with an \cw{x}):
+
+\c  -------- 
+\c |........|
+\c |........|
+\c |..O..O..|
+\c |...xx...|
+\c |...xx...|
+\c |..O..O..|
+\c |........|
+\c |........|
+\c  --------
+
+For this reason, when you have your guesses checked, the game will
+check that your solution \e{produces the same results} as the
+computer's, rather than that your solution is identical to the
+computer's. So in the above example, you could put the fifth ball at
+\e{any} of the locations marked with an \cw{x}, and you would still
+win.
+
+Black Box was contributed to this collection by James Harvey.
+
+\H{blackbox-controls} \i{Black Box controls}
+
+\IM{Black Box controls} controls, for Black Box
+\IM{Black Box controls} keys, for Black Box
+\IM{Black Box controls} shortcuts (keyboard), for Black Box
+
+To fire a laser beam, left-click in a square around the edge of the
+arena. The results will be displayed immediately. Clicking or holding
+the left button on one of these squares will highlight the current go
+(or a previous go) to confirm the exit point for that laser, if
+applicable.
+
+To guess the location of a ball, left-click within the arena and a
+black circle will appear marking the guess; click again to remove the
+guessed ball.
+
+Locations in the arena may be locked against modification by
+right-clicking; whole rows and columns may be similarly locked by
+right-clicking in the laser square above/below that column, or to the
+left/right of that row.
+
+The cursor keys may also be used to move around the grid. Pressing the
+Enter key will fire a laser or add a new ball-location guess, and
+pressing Space will lock a cell, row, or column.
+
+When an appropriate number of balls have been guessed, a button will
+appear at the top-left corner of the grid; clicking that (with mouse
+or cursor) will check your guesses. 
+
+If you click the \q{check} button and your guesses are not correct,
+the game will show you the minimum information necessary to
+demonstrate this to you, so you can try again. If your ball
+positions are not consistent with the beam paths you already know
+about, one beam path will be circled to indicate that it proves you
+wrong. If your positions match all the existing beam paths but are
+still wrong, one new beam path will be revealed (written in red)
+which is not consistent with your current guesses.
+
+If you decide to give up completely, you can select Solve to reveal
+the actual ball positions. At this point, correctly-placed balls
+will be displayed as filled black circles, incorrectly-placed balls
+as filled black circles with red crosses, and missing balls as filled
+red circles. In addition, a red circle marks any laser you had already
+fired which is not consistent with your ball layout (just as when you
+press the \q{check} button), and red text marks any laser you
+\e{could} have fired in order to distinguish your ball layout from the
+correct one.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{blackbox-parameters} \I{parameters, for Black Box}Black Box parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares. There are 2 \by \e{Width} \by \e{Height} lasers 
+per grid, two per row and two per column. 
+
+\dt \e{No. of balls}
+
+\dd Number of balls to place in the grid. This can be a single number,
+or a range (separated with a hyphen, like \q{2-6}), and determines the
+number of balls to place on the grid. The \q{reveal} button is only
+enabled if you have guessed an appropriate number of balls; a guess
+using a different number to the original solution is still acceptable,
+if all the beam inputs and outputs match.
+
+
+\C{slant} \i{Slant}
+
+\cfg{winhelp-topic}{games.slant}
+
+You have a grid of squares. Your aim is to draw a diagonal line
+through each square, and choose which way each line slants so that
+the following conditions are met:
+
+\b The diagonal lines never form a loop.
+
+\b Any point with a circled number has precisely that many lines
+meeting at it. (Thus, a 4 is the centre of a cross shape, whereas a
+zero is the centre of a diamond shape \dash or rather, a partial
+diamond shape, because a zero can never appear in the middle of the
+grid because that would immediately cause a loop.)
+
+Credit for this puzzle goes to \i{Nikoli} \k{nikoli-slant}.
+
+\B{nikoli-slant}
+\W{http://www.nikoli.co.jp/ja/puzzles/gokigen_naname}\cw{http://www.nikoli.co.jp/ja/puzzles/gokigen_naname}
+(in Japanese)
+
+\H{slant-controls} \i{Slant controls}
+
+\IM{Slant controls} controls, for Slant
+
+Left-clicking in a blank square will place a \cw{\\} in it (a line
+leaning to the left, i.e. running from the top left of the square to
+the bottom right). Right-clicking in a blank square will place a
+\cw{/} in it (leaning to the right, running from top right to bottom
+left).
+
+Continuing to click either button will cycle between the three
+possible square contents. Thus, if you left-click repeatedly in a
+blank square it will change from blank to \cw{\\} to \cw{/} back to
+blank, and if you right-click repeatedly the square will change from
+blank to \cw{/} to \cw{\\} back to blank. (Therefore, you can play
+the game entirely with one button if you need to.)
+
+You can also use the cursor keys to move around the grid. Pressing the
+return or space keys will place a \cw{\\} or a \cw{/}, respectively,
+and will then cycle them as above.  You can also press \cw{/} or
+\cw{\\} to place a \cw{/} or \cw{\\}, respectively, independent of
+what is already in the cursor square.  Backspace removes any line from
+the cursor square.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{slant-parameters} \I{parameters, for Slant}Slant parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle. At Hard level,
+you are required to do deductions based on knowledge of
+\e{relationships} between squares rather than always being able to
+deduce the exact contents of one square at a time. (For example, you
+might know that two squares slant in the same direction, even if you
+don't yet know what that direction is, and this might enable you to
+deduce something about still other squares.) Even at Hard level,
+guesswork and backtracking should never be necessary.
+
+
+\C{lightup} \i{Light Up}
+
+\cfg{winhelp-topic}{games.lightup}
+
+You have a grid of squares. Some are filled in black; some of the
+black squares are numbered. Your aim is to \q{light up} all the
+empty squares by placing light bulbs in some of them.
+
+Each light bulb illuminates the square it is on, plus all squares in
+line with it horizontally or vertically unless a black square is
+blocking the way.
+
+To win the game, you must satisfy the following conditions:
+
+\b All non-black squares are lit.
+
+\b No light is lit by another light.
+
+\b All numbered black squares have exactly that number of lights adjacent to
+   them (in the four squares above, below, and to the side).
+
+Non-numbered black squares may have any number of lights adjacent to them. 
+
+Credit for this puzzle goes to \i{Nikoli} \k{nikoli-lightup}.
+
+Light Up was contributed to this collection by James Harvey.
+
+\B{nikoli-lightup}
+\W{http://www.nikoli.co.jp/en/puzzles/akari.html}\cw{http://www.nikoli.co.jp/en/puzzles/akari.html}
+(beware of Flash)
+
+\H{lightup-controls} \i{Light Up controls}
+
+\IM{Light Up controls} controls, for Light Up
+
+Left-clicking in a non-black square will toggle the presence of a light
+in that square. Right-clicking in a non-black square toggles a mark there to aid
+solving; it can be used to highlight squares that cannot be lit, for example. 
+
+You may not place a light in a marked square, nor place a mark in a lit square.
+
+The game will highlight obvious errors in red. Lights lit by other
+lights are highlighted in this way, as are numbered squares which
+do not (or cannot) have the right number of lights next to them.
+  
+Thus, the grid is solved when all non-black squares have yellow
+highlights and there are no red lights.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{lightup-parameters} \I{parameters, for Light Up}Light Up parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{%age of black squares}
+
+\dd Rough percentage of black squares in the grid.
+
+\lcont{
+
+This is a hint rather than an instruction. If the grid generator is
+unable to generate a puzzle to this precise specification, it will
+increase the proportion of black squares until it can.
+
+}
+
+\dt \e{Symmetry}
+
+\dd Allows you to specify the required symmetry of the black squares
+in the grid. (This does not affect the difficulty of the puzzles
+noticeably.)
+
+\dt \e{Difficulty}
+
+\dd \q{Easy} means that the puzzles should be soluble without
+backtracking or guessing, \q{Hard} means that some guesses will
+probably be necessary.
+
+
+\C{map} \i{Map}
+
+\cfg{winhelp-topic}{games.map}
+
+You are given a map consisting of a number of regions. Your task is
+to colour each region with one of four colours, in such a way that
+no two regions sharing a boundary have the same colour. You are
+provided with some regions already coloured, sufficient to make the
+remainder of the solution unique.
+
+Only regions which share a length of border are required to be
+different colours. Two regions which meet at only one \e{point}
+(i.e. are diagonally separated) may be the same colour.
+
+I believe this puzzle is original; I've never seen an implementation
+of it anywhere else. The concept of a \i{four-colouring} puzzle was
+suggested by Owen Dunn; credit must also go to Nikoli and to Verity
+Allan for inspiring the train of thought that led to me realising
+Owen's suggestion was a viable puzzle. Thanks also to Gareth Taylor
+for many detailed suggestions.
+
+\H{map-controls} \i{Map controls}
+
+\IM{Map controls} controls, for Map
+
+To colour a region, click the left mouse button on an existing
+region of the desired colour and drag that colour into the new
+region.
+
+(The program will always ensure the starting puzzle has at least one
+region of each colour, so that this is always possible!)
+
+If you need to clear a region, you can drag from an empty region, or
+from the puzzle boundary if there are no empty regions left.
+
+Dragging a colour using the \e{right} mouse button will stipple the
+region in that colour, which you can use as a note to yourself that
+you think the region \e{might} be that colour. A region can contain
+stipples in multiple colours at once. (This is often useful at the
+harder difficulty levels.)
+
+You can also use the cursor keys to move around the map: the colour of
+the cursor indicates the position of the colour you would drag (which
+is not obvious if you're on a region's boundary, since it depends on the
+direction from which you approached the boundary). Pressing the return
+key starts a drag of that colour, as above, which you control with the
+cursor keys; pressing the return key again finishes the drag. The
+space bar can be used similarly to create a stippled region. 
+Double-pressing the return key (without moving the cursor) will clear
+the region, as a drag from an empty region does: this is useful with
+the cursor mode if you have filled the entire map in but need to 
+correct the layout.
+
+If you press L during play, the game will toggle display of a number
+in each region of the map. This is useful if you want to discuss a
+particular puzzle instance with a friend \dash having an unambiguous
+name for each region is much easier than trying to refer to them all
+by names such as \q{the one down and right of the brown one on the
+top border}.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{map-parameters} \I{parameters, for Map}Map parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Regions}
+
+\dd Number of regions in the generated map.
+
+\dt \e{Difficulty}
+
+\dd In \q{Easy} mode, there should always be at least one region
+whose colour can be determined trivially. In \q{Normal} and \q{Hard}
+modes, you will have to use increasingly complex logic to deduce the
+colour of some regions. However, it will always be possible without
+having to guess or backtrack.
+
+\lcont{
+
+In \q{Unreasonable} mode, the program will feel free to generate
+puzzles which are as hard as it can possibly make them: the only
+constraint is that they should still have a unique solution. Solving
+Unreasonable puzzles may require guessing and backtracking.
+
+}
+
+
+\C{loopy} \i{Loopy}
+
+\cfg{winhelp-topic}{games.loopy}
+
+You are given a grid of dots, marked with yellow lines to indicate
+which dots you are allowed to connect directly together. Your aim is
+to use some subset of those yellow lines to draw a single unbroken
+loop from dot to dot within the grid.
+
+Some of the spaces between the lines contain numbers. These numbers
+indicate how many of the lines around that space form part of the
+loop. The loop you draw must correctly satisfy all of these clues to
+be considered a correct solution.
+
+In the default mode, the dots are arranged in a grid of squares;
+however, you can also play on triangular or hexagonal grids, or even
+more exotic ones.
+
+Credit for the basic puzzle idea goes to \i{Nikoli}
+\k{nikoli-loopy}.
+
+Loopy was originally contributed to this collection by Mike Pinna,
+and subsequently enhanced to handle various types of non-square grid
+by Lambros Lambrou.
+
+\B{nikoli-loopy}
+\W{http://www.nikoli.co.jp/en/puzzles/slitherlink.html}\cw{http://www.nikoli.co.jp/en/puzzles/slitherlink.html}
+(beware of Flash)
+
+\H{loopy-controls} \i{Loopy controls}
+
+\IM{Loopy controls} controls, for Loopy
+
+Click the left mouse button on a yellow line to turn it black,
+indicating that you think it is part of the loop. Click again to
+turn the line yellow again (meaning you aren't sure yet).
+
+If you are sure that a particular line segment is \e{not} part of
+the loop, you can click the right mouse button to remove it
+completely. Again, clicking a second time will turn the line back to
+yellow.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{loopy-parameters} \I{parameters, for Loopy}Loopy parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid, measured in number of regions across and down. For
+square grids, it's clear how this is counted; for other types of
+grid you may have to think a bit to see how the dimensions are
+measured.
+
+\dt \e{Grid type}
+
+\dd Allows you to choose between a selection of types of tiling.
+Some have all the faces the same but may have multiple different
+types of vertex (e.g. the \e{Cairo} or \e{Kites} mode); others have
+all the vertices the same but may have different types of face (e.g.
+the \e{Great Hexagonal}). The square, triangular and honeycomb grids
+are fully regular, and have all their vertices \e{and} faces the
+same; this makes them the least confusing to play.
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle.
+\#{FIXME: what distinguishes Easy, Medium, and Hard? In particular,
+when are backtracking/guesswork required, if ever?}
+
+
+\C{inertia} \i{Inertia}
+
+\cfg{winhelp-topic}{games.inertia}
+
+You are a small green ball sitting in a grid full of obstacles. Your
+aim is to collect all the gems without running into any mines.
+
+You can move the ball in any orthogonal \e{or diagonal} direction.
+Once the ball starts moving, it will continue until something stops
+it. A wall directly in its path will stop it (but if it is moving
+diagonally, it will move through a diagonal gap between two other
+walls without stopping). Also, some of the squares are \q{stops};
+when the ball moves on to a stop, it will stop moving no matter what
+direction it was going in. Gems do \e{not} stop the ball; it picks
+them up and keeps on going.
+
+Running into a mine is fatal. Even if you picked up the last gem in
+the same move which then hit a mine, the game will count you as dead
+rather than victorious.
+
+This game was originally implemented for Windows by Ben Olmstead
+\k{bem}, who was kind enough to release his source code on request
+so that it could be re-implemented for this collection.
+
+\B{bem} \W{http://xn13.com/}\cw{http://xn13.com/}
+
+\H{inertia-controls} \i{Inertia controls}
+
+\IM{Inertia controls} controls, for Inertia
+\IM{Inertia controls} keys, for Inertia
+\IM{Inertia controls} shortcuts (keyboard), for Inertia
+
+You can move the ball in any of the eight directions using the
+numeric keypad. Alternatively, if you click the left mouse button on
+the grid, the ball will begin a move in the general direction of
+where you clicked.
+
+If you use the \q{Solve} function on this game, the program will
+compute a path through the grid which collects all the remaining
+gems and returns to the current position. A hint arrow will appear
+on the ball indicating the direction in which you should move to
+begin on this path. If you then move in that direction, the arrow
+will update to indicate the next direction on the path. You can also
+press Space to automatically move in the direction of the hint
+arrow. If you move in a different direction from the one shown by
+the arrow, arrows will be shown only if the puzzle is still solvable.
+
+All the actions described in \k{common-actions} are also available.
+In particular, if you do run into a mine and die, you can use the
+Undo function and resume playing from before the fatal move. The
+game will keep track of the number of times you have done this.
+
+\H{inertia-parameters} \I{parameters, for Inertia}Inertia parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+
+\C{tents} \i{Tents}
+
+\cfg{winhelp-topic}{games.tents}
+
+You have a grid of squares, some of which contain trees. Your aim is
+to place tents in some of the remaining squares, in such a way that
+the following conditions are met:
+
+\b There are exactly as many tents as trees.
+
+\b The tents and trees can be matched up in such a way that each
+tent is directly adjacent (horizontally or vertically, but not
+diagonally) to its own tree. However, a tent may be adjacent to
+other trees as well as its own.
+
+\b No two tents are adjacent horizontally, vertically \e{or
+diagonally}.
+
+\b The number of tents in each row, and in each column, matches the
+numbers given round the sides of the grid.
+
+This puzzle can be found in several places on the Internet, and was
+brought to my attention by e-mail. I don't know who I should credit
+for inventing it.
+
+\H{tents-controls} \i{Tents controls}
+
+\IM{Tents controls} controls, for Tents
+
+Left-clicking in a blank square will place a tent in it.
+Right-clicking in a blank square will colour it green, indicating
+that you are sure it \e{isn't} a tent. Clicking either button in an
+occupied square will clear it.
+
+If you \e{drag} with the right button along a row or column, every
+blank square in the region you cover will be turned green, and no
+other squares will be affected. (This is useful for clearing the
+remainder of a row once you have placed all its tents.)
+
+You can also use the cursor keys to move around the grid. Pressing the
+return key over an empty square will place a tent, and pressing the
+space bar over an empty square will colour it green; either key will
+clear an occupied square.  Holding Shift and pressing the cursor keys
+will colour empty squares green.  Holding Control and pressing the
+cursor keys will colour green both empty squares and squares with tents.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{tents-parameters} \I{parameters, for Tents}Tents parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle. More difficult
+puzzles require more complex deductions, but at present none of the
+available difficulty levels requires guesswork or backtracking.
+
+
+\C{bridges} \i{Bridges}
+
+\cfg{winhelp-topic}{games.bridges}
+
+You have a set of islands distributed across the playing area. Each
+island contains a number. Your aim is to connect the islands
+together with bridges, in such a way that:
+
+\b Bridges run horizontally or vertically.
+
+\b The number of bridges terminating at any island is equal to the
+number written in that island.
+
+\b Two bridges may run in parallel between the same two islands, but
+no more than two may do so.
+
+\b No bridge crosses another bridge.
+
+\b All the islands are connected together.
+
+There are some configurable alternative modes, which involve
+changing the parallel-bridge limit to something other than 2, and
+introducing the additional constraint that no sequence of bridges
+may form a loop from one island back to the same island. The rules
+stated above are the default ones.
+
+Credit for this puzzle goes to \i{Nikoli} \k{nikoli-bridges}.
+
+Bridges was contributed to this collection by James Harvey.
+
+\B{nikoli-bridges}
+\W{http://www.nikoli.co.jp/en/puzzles/hashiwokakero.html}\cw{http://www.nikoli.co.jp/en/puzzles/hashiwokakero.html}
+(beware of Flash)
+
+\H{bridges-controls} \i{Bridges controls}
+
+\IM{Bridges controls} controls, for Bridges
+
+To place a bridge between two islands, click the mouse down on one
+island and drag it towards the other. You do not need to drag all
+the way to the other island; you only need to move the mouse far
+enough for the intended bridge direction to be unambiguous. (So you
+can keep the mouse near the starting island and conveniently throw
+bridges out from it in many directions.)
+
+Doing this again when a bridge is already present will add another
+parallel bridge. If there are already as many bridges between the
+two islands as permitted by the current game rules (i.e. two by
+default), the same dragging action will remove all of them.
+
+If you want to remind yourself that two islands definitely \e{do
+not} have a bridge between them, you can right-drag between them in
+the same way to draw a \q{non-bridge} marker.
+
+If you think you have finished with an island (i.e. you have placed
+all its bridges and are confident that they are in the right
+places), you can mark the island as finished by left-clicking on it.
+This will highlight it and all the bridges connected to it, and you
+will be prevented from accidentally modifying any of those bridges
+in future. Left-clicking again on a highlighted island will unmark
+it and restore your ability to modify it.
+
+You can also use the cursor keys to move around the grid: if possible
+the cursor will always move orthogonally, otherwise it will move
+towards the nearest island to the indicated direction. Holding Control
+and pressing a cursor key will lay a bridge in that direction (if
+available); Shift and a cursor key will lay a \q{non-bridge} marker.
+Pressing the return key followed by a cursor key will also lay a
+bridge in that direction.
+
+You can mark an island as finished by pressing the space bar or by
+pressing the return key twice.
+
+By pressing a number key, you can jump to the nearest island with that
+number.  Letters \q{a}, ..., \q{f} count as 10, ..., 15 and \q{0} as
+16.
+
+Violations of the puzzle rules will be marked in red:
+
+\b An island with too many bridges will be highlighted in red.
+
+\b An island with too few bridges will be highlighted in red if it
+is definitely an error (as opposed to merely not being finished
+yet): if adding enough bridges would involve having to cross another
+bridge or remove a non-bridge marker, or if the island has been
+highlighted as complete.
+
+\b A group of islands and bridges may be highlighted in red if it is
+a closed subset of the puzzle with no way to connect it to the rest
+of the islands. For example, if you directly connect two 1s together
+with a bridge and they are not the only two islands on the grid,
+they will light up red to indicate that such a group cannot be
+contained in any valid solution.
+
+\b If you have selected the (non-default) option to disallow loops
+in the solution, a group of bridges which forms a loop will be
+highlighted.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{bridges-parameters} \I{parameters, for Bridges}Bridges parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Difficulty}
+
+\dd Difficulty level of puzzle.
+
+\dt \e{Allow loops}
+
+\dd This is set by default. If cleared, puzzles will be generated in
+such a way that they are always soluble without creating a loop, and
+solutions which do involve a loop will be disallowed.
+
+\dt \e{Max. bridges per direction}
+
+\dd Maximum number of bridges in any particular direction. The
+default is 2, but you can change it to 1, 3 or 4. In general, fewer
+is easier.
+
+\dt \e{%age of island squares}
+
+\dd Gives a rough percentage of islands the generator will try and
+lay before finishing the puzzle. Certain layouts will not manage to
+lay enough islands; this is an upper bound.
+
+\dt \e{Expansion factor (%age)}
+
+\dd The grid generator works by picking an existing island at random
+(after first creating an initial island somewhere). It then decides
+on a direction (at random), and then works out how far it could
+extend before creating another island. This parameter determines how
+likely it is to extend as far as it can, rather than choosing
+somewhere closer.
+
+\lcont{
+
+High expansion factors usually mean easier puzzles with fewer
+possible islands; low expansion factors can create lots of
+tightly-packed islands.
+
+}
+
+
+\C{unequal} \i{Unequal}
+
+\cfg{winhelp-topic}{games.unequal}
+
+You have a square grid; each square may contain a digit from 1 to
+the size of the grid, and some squares have clue signs between
+them. Your aim is to fully populate the grid with numbers such that:
+
+\b Each row contains only one occurrence of each digit
+
+\b Each column contains only one occurrence of each digit
+
+\b All the clue signs are satisfied. 
+
+There are two modes for this game, \q{Unequal} and \q{Adjacent}.
+
+In \q{Unequal} mode, the clue signs are greater-than symbols indicating one
+square's value is greater than its neighbour's. In this mode not all clues
+may be visible, particularly at higher difficulty levels. 
+
+In \q{Adjacent} mode, the clue signs are bars indicating
+one square's value is numerically adjacent (i.e. one higher or one lower)
+than its neighbour. In this mode all clues are always visible: absence of
+a bar thus means that a square's value is definitely not numerically adjacent
+to that neighbour's.  
+
+In \q{Trivial} difficulty level (available via the \q{Custom} game type
+selector), there are no greater-than signs in \q{Unequal} mode; the puzzle is
+to solve the \i{Latin square} only.
+
+At the time of writing, the \q{Unequal} mode of this puzzle is appearing in the
+Guardian weekly under the name \q{\i{Futoshiki}}.
+
+Unequal was contributed to this collection by James Harvey.
+
+\H{unequal-controls} \i{Unequal controls}
+
+\IM{Unequal controls} controls, for Unequal
+
+Unequal shares much of its control system with Solo.
+
+To play Unequal, simply click the mouse in any empty square and then
+type a digit or letter on the keyboard to fill that square. If you
+make a mistake, click the mouse in the incorrect square and press
+Space to clear it again (or use the Undo feature).
+
+If you \e{right}-click in a square and then type a number, that
+number will be entered in the square as a \q{pencil mark}. You can
+have pencil marks for multiple numbers in the same square. Squares
+containing filled-in numbers cannot also contain pencil marks.
+
+The game pays no attention to pencil marks, so exactly what you use
+them for is up to you: you can use them as reminders that a
+particular square needs to be re-examined once you know more about a
+particular number, or you can use them as lists of the possible
+numbers in a given square, or anything else you feel like.
+
+To erase a single pencil mark, right-click in the square and type
+the same number again.
+
+All pencil marks in a square are erased when you left-click and type
+a number, or when you left-click and press space. Right-clicking and
+pressing space will also erase pencil marks.
+
+As for Solo, the cursor keys can be used in conjunction with the digit
+keys to set numbers or pencil marks. You can also use the \q{M} key to
+auto-fill every numeric hint, ready for removal as required, or the \q{H}
+key to do the same but also to remove all obvious hints. 
+
+Alternatively, use the cursor keys to move the mark around the grid.
+Pressing the return key toggles the mark (from a normal mark to a
+pencil mark), and typing a number in is entered in the square in the
+appropriate way; typing in a 0 or using the space bar will clear a
+filled square. 
+
+Left-clicking a clue will mark it as done (grey it out), or unmark it
+if it is already marked.  Holding Control or Shift and pressing an
+arrow key likewise marks any clue adjacent to the cursor in the given
+direction.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{unequal-parameters} \I{parameters, for Unequal}Unequal parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Mode}
+
+\dd Mode of the puzzle (\q{Unequal} or \q{Adjacent})
+
+\dt \e{Size (s*s)}
+
+\dd Size of grid.
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle. At Trivial
+level, there are no greater-than signs; the puzzle is to solve the
+Latin square only. At Recursive level (only available via the
+\q{Custom} game type selector) backtracking will be required, but
+the solution should still be unique. The levels in between require
+increasingly complex reasoning to avoid having to backtrack.
+
+
+
+\C{galaxies} \i{Galaxies}
+
+\cfg{winhelp-topic}{games.galaxies}
+
+You have a rectangular grid containing a number of dots. Your aim is
+to draw edges along the grid lines which divide the rectangle into
+regions in such a way that every region is 180\u00b0{-degree}
+rotationally symmetric, and contains exactly one dot which is
+located at its centre of symmetry.
+
+This puzzle was invented by \i{Nikoli} \k{nikoli-galaxies}, under
+the name \q{Tentai Show}; its name is commonly translated into
+English as \q{Spiral Galaxies}.
+
+Galaxies was contributed to this collection by James Harvey.
+
+\B{nikoli-galaxies} \W{http://www.nikoli.co.jp/en/puzzles/astronomical_show.html}\cw{http://www.nikoli.co.jp/en/puzzles/astronomical_show.html}
+
+\H{galaxies-controls} \i{Galaxies controls}
+
+\IM{Galaxies controls} controls, for Galaxies
+
+Left-click on any grid line to draw an edge if there isn't one
+already, or to remove one if there is. When you create a valid
+region (one which is closed, contains exactly one dot, is
+180\u00b0{-degree} symmetric about that dot, and contains no
+extraneous edges inside it) it will be highlighted automatically; so
+your aim is to have the whole grid highlighted in that way.
+
+During solving, you might know that a particular grid square belongs
+to a specific dot, but not be sure of where the edges go and which
+other squares are connected to the dot. In order to mark this so you
+don't forget, you can right-click on the dot and drag, which will
+create an arrow marker pointing at the dot. Drop that in a square of
+your choice and it will remind you which dot it's associated with.
+You can also right-click on existing arrows to pick them up and move
+them, or destroy them by dropping them off the edge of the grid.
+(Also, if you're not sure which dot an arrow is pointing at, you can
+pick it up and move it around to make it clearer. It will swivel
+constantly as you drag it, to stay pointed at its parent dot.)
+
+You can also use the cursor keys to move around the grid squares and
+lines.  Pressing the return key when over a grid line will draw or
+clear its edge, as above. Pressing the return key when over a dot will
+pick up an arrow, to be dropped the next time the return key is
+pressed; this can also be used to move existing arrows around, removing
+them by dropping them on a dot or another arrow.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{galaxies-parameters} \I{parameters, for Galaxies}Galaxies parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle. More difficult
+puzzles require more complex deductions, and the \q{Unreasonable}
+difficulty level may require backtracking.
+
+
+
+\C{filling} \i{Filling}
+
+\cfg{winhelp-topic}{games.filling}
+
+You have a grid of squares, some of which contain digits, and the
+rest of which are empty. Your job is to fill in digits in the empty
+squares, in such a way that each connected region of squares all
+containing the same digit has an area equal to that digit.
+
+(\q{Connected region}, for the purposes of this game, does not count
+diagonally separated squares as adjacent.)
+
+For example, it follows that no square can contain a zero, and that
+two adjacent squares can not both contain a one.  No region has an
+area greater than 9 (because then its area would not be a single
+digit).
+
+Credit for this puzzle goes to \i{Nikoli} \k{nikoli-fillomino}.
+
+Filling was contributed to this collection by Jonas K\u00F6{oe}lker.
+
+\B{nikoli-fillomino}
+\W{http://www.nikoli.co.jp/en/puzzles/fillomino.html}\cw{http://www.nikoli.co.jp/en/puzzles/fillomino.html}
+
+\H{filling-controls} \I{controls, for Filling}Filling controls
+
+To play Filling, simply click the mouse in any empty square and then
+type a digit on the keyboard to fill that square. By dragging the
+mouse, you can select multiple squares to fill with a single keypress.
+If you make a mistake, click the mouse in the incorrect square and
+press 0, Space, Backspace or Enter to clear it again (or use the Undo
+feature).
+
+You can also move around the grid with the cursor keys; typing a digit will
+fill the square containing the cursor with that number; typing 0 will clear
+it.  You can also select multiple squares for numbering or clearing with the
+return and arrow keys, before typing a digit to fill or clear the highlighted
+squares (as above).  The space bar adds and removes single squares to and from
+the selection.  Backspace and escape remove all squares from the selection.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{filling-parameters} \I{parameters, for Filling}Filling parameters
+
+Filling allows you to configure the number of rows and columns of the
+grid, through the \q{Type} menu.
+
+
+\C{keen} \i{Keen}
+
+\cfg{winhelp-topic}{games.keen}
+
+You have a square grid; each square may contain a digit from 1 to
+the size of the grid. The grid is divided into blocks of varying
+shape and size, with arithmetic clues written in them. Your aim is
+to fully populate the grid with digits such that:
+
+\b Each row contains only one occurrence of each digit
+
+\b Each column contains only one occurrence of each digit
+
+\b The digits in each block can be combined to form the number
+stated in the clue, using the arithmetic operation given in the
+clue. That is:
+
+\lcont{
+
+\b An addition clue means that the sum of the digits in the block
+must be the given number. For example, \q{15+} means the contents of
+the block adds up to fifteen.
+
+\b A multiplication clue (e.g. \q{60\times}), similarly, means that
+the product of the digits in the block must be the given number.
+
+\b A subtraction clue will always be written in a block of size two,
+and it means that one of the digits in the block is greater than the
+other by the given amount. For example, \q{2\minus} means that one
+of the digits in the block is 2 more than the other, or equivalently
+that one digit minus the other one is 2. The two digits could be
+either way round, though.
+
+\b A division clue (e.g. \q{3\divide}), similarly, is always in a
+block of size two and means that one digit divided by the other is
+equal to the given amount.
+
+Note that a block may contain the same digit more than once
+(provided the identical ones are not in the same row and column).
+This rule is precisely the opposite of the rule in Solo's \q{Killer}
+mode (see \k{solo}).
+
+}
+
+This puzzle appears in the Times under the name \q{\i{KenKen}}.
+
+
+\H{keen-controls} \i{Keen controls}
+
+\IM{Keen controls} controls, for Keen
+
+Keen shares much of its control system with Solo (and Unequal).
+
+To play Keen, simply click the mouse in any empty square and then
+type a digit on the keyboard to fill that square. If you make a
+mistake, click the mouse in the incorrect square and press Space to
+clear it again (or use the Undo feature).
+
+If you \e{right}-click in a square and then type a number, that
+number will be entered in the square as a \q{pencil mark}. You can
+have pencil marks for multiple numbers in the same square. Squares
+containing filled-in numbers cannot also contain pencil marks.
+
+The game pays no attention to pencil marks, so exactly what you use
+them for is up to you: you can use them as reminders that a
+particular square needs to be re-examined once you know more about a
+particular number, or you can use them as lists of the possible
+numbers in a given square, or anything else you feel like.
+
+To erase a single pencil mark, right-click in the square and type
+the same number again.
+
+All pencil marks in a square are erased when you left-click and type
+a number, or when you left-click and press space. Right-clicking and
+pressing space will also erase pencil marks.
+
+As for Solo, the cursor keys can be used in conjunction with the
+digit keys to set numbers or pencil marks. Use the cursor keys to
+move a highlight around the grid, and type a digit to enter it in
+the highlighted square. Pressing return toggles the highlight into a
+mode in which you can enter or remove pencil marks.
+
+Pressing M will fill in a full set of pencil marks in every square
+that does not have a main digit in it.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{keen-parameters} \I{parameters, for Keen}Keen parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Grid size}
+
+\dd Specifies the size of the grid. Lower limit is 3; upper limit is
+9 (because the user interface would become more difficult with
+\q{digits} bigger than 9!).
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle. At Unreasonable
+level, some backtracking will be required, but the solution should
+still be unique. The remaining levels require increasingly complex
+reasoning to avoid having to backtrack.
+
+\dt \e{Multiplication only}
+
+\dd If this is enabled, all boxes will be multiplication boxes.
+With this rule, the puzzle is known as \q{Inshi No Heya}.
+
+\C{towers} \i{Towers}
+
+\cfg{winhelp-topic}{games.towers}
+
+You have a square grid. On each square of the grid you can build a
+tower, with its height ranging from 1 to the size of the grid.
+Around the edge of the grid are some numeric clues.
+
+Your task is to build a tower on every square, in such a way that:
+
+\b Each row contains every possible height of tower once
+
+\b Each column contains every possible height of tower once
+
+\b Each numeric clue describes the number of towers that can be seen
+if you look into the square from that direction, assuming that
+shorter towers are hidden behind taller ones. For example, in a
+5\by\.5 grid, a clue marked \q{5} indicates that the five tower
+heights must appear in increasing order (otherwise you would not be
+able to see all five towers), whereas a clue marked \q{1} indicates
+that the tallest tower (the one marked 5) must come first.
+
+In harder or larger puzzles, some towers will be specified for you
+as well as the clues round the edge, and some edge clues may be
+missing.
+
+This puzzle appears on the web under various names, particularly
+\q{\i{Skyscrapers}}, but I don't know who first invented it.
+
+
+\H{towers-controls} \i{Towers controls}
+
+\IM{Towers controls} controls, for Towers
+
+Towers shares much of its control system with Solo, Unequal and Keen.
+
+To play Towers, simply click the mouse in any empty square and then
+type a digit on the keyboard to fill that square with a tower of the
+given height. If you make a mistake, click the mouse in the
+incorrect square and press Space to clear it again (or use the Undo
+feature).
+
+If you \e{right}-click in a square and then type a number, that
+number will be entered in the square as a \q{pencil mark}. You can
+have pencil marks for multiple numbers in the same square. A square
+containing a tower cannot also contain pencil marks.
+
+The game pays no attention to pencil marks, so exactly what you use
+them for is up to you: you can use them as reminders that a
+particular square needs to be re-examined once you know more about a
+particular number, or you can use them as lists of the possible
+numbers in a given square, or anything else you feel like.
+
+To erase a single pencil mark, right-click in the square and type
+the same number again.
+
+All pencil marks in a square are erased when you left-click and type
+a number, or when you left-click and press space. Right-clicking and
+pressing space will also erase pencil marks.
+
+As for Solo, the cursor keys can be used in conjunction with the
+digit keys to set numbers or pencil marks. Use the cursor keys to
+move a highlight around the grid, and type a digit to enter it in
+the highlighted square. Pressing return toggles the highlight into a
+mode in which you can enter or remove pencil marks.
+
+Pressing M will fill in a full set of pencil marks in every square
+that does not have a main digit in it.
+
+Left-clicking a clue will mark it as done (grey it out), or unmark it
+if it is already marked.  Holding Control or Shift and pressing an
+arrow key likewise marks any clue in the given direction.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{towers-parameters} \I{parameters, for Towers}Towers parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Grid size}
+
+\dd Specifies the size of the grid. Lower limit is 3; upper limit is
+9 (because the user interface would become more difficult with
+\q{digits} bigger than 9!).
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle. At Unreasonable
+level, some backtracking will be required, but the solution should
+still be unique. The remaining levels require increasingly complex
+reasoning to avoid having to backtrack.
+
+
+\C{singles} \i{Singles}
+
+\cfg{winhelp-topic}{games.singles}
+
+You have a grid of white squares, all of which contain numbers. Your task
+is to colour some of the squares black (removing the number) so as to satisfy
+all of the following conditions:
+
+\b No number occurs more than once in any row or column.
+
+\b No black square is horizontally or vertically adjacent to any other black
+square.
+
+\b The remaining white squares must all form one contiguous region
+(connected by edges, not just touching at corners).
+
+Credit for this puzzle goes to \i{Nikoli} \k{nikoli-hitori} who call it
+\i{Hitori}. 
+
+Singles was contributed to this collection by James Harvey.
+
+\B{nikoli-hitori}
+\W{http://www.nikoli.com/en/puzzles/hitori.html}\cw{http://www.nikoli.com/en/puzzles/hitori.html}
+(beware of Flash)
+
+\H{singles-controls} \i{Singles controls}
+
+\IM{Singles controls} controls, for Singles
+
+Left-clicking on an empty square will colour it black; left-clicking again 
+will restore the number. Right-clicking will add a circle (useful for 
+indicating that a cell is definitely not black). 
+
+You can also use the cursor keys to move around the grid. Pressing the
+return or space keys will turn a square black or add a circle respectively,
+and pressing the key again will restore the number or remove the circle.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{singles-parameters} \I{parameters, for Singles}Singles parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle.
+
+
+\C{magnets} \i{Magnets}
+
+\cfg{winhelp-topic}{games.magnets}
+
+A rectangular grid has been filled with a mixture of magnets (that is,
+dominoes with one positive end and one negative end) and blank dominoes
+(that is, dominoes with two neutral poles).
+These dominoes are initially only seen in silhouette. Around the grid
+are placed a number of clues indicating the number of positive and
+negative poles contained in certain columns and rows.
+
+Your aim is to correctly place the magnets and blank dominoes such that
+all the clues are satisfied, with the additional constraint that no two
+similar magnetic poles may be orthogonally adjacent (since they repel).
+Neutral poles do not repel, and can be adjacent to any other pole. 
+
+Credit for this puzzle goes to \i{Janko} \k{janko-magnets}.
+
+Magnets was contributed to this collection by James Harvey.
+
+\B{janko-magnets}
+\W{http://www.janko.at/Raetsel/Magnete/index.htm}\cw{http://www.janko.at/Raetsel/Magnete/index.htm}
+
+\H{magnets-controls} \i{Magnets controls}
+
+\IM{Magnets controls} controls, for Magnets
+
+Left-clicking on an empty square places a magnet at that position with
+the positive pole on the square and the negative pole on the other half
+of the magnet; left-clicking again reverses the polarity, and a third
+click removes the magnet.
+
+Right-clicking on an empty square places a blank domino there.
+Right-clicking again places two question marks on the domino, signifying
+\q{this cannot be blank} (which can be useful to note deductions while
+solving), and right-clicking again empties the domino. 
+
+Left-clicking a clue will mark it as done (grey it out), or unmark it if
+it is already marked.
+
+You can also use the cursor keys to move a cursor around the grid. 
+Pressing the return key will lay a domino with a positive pole at that
+position; pressing again reverses the polarity and then removes the
+domino, as with left-clicking. Using the space bar allows placement
+of blank dominoes and cannot-be-blank hints, as for right-clicking. 
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{magnets-parameters} \I{parameters, for Magnets}Magnets parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares. There will be half \e{Width} \by \e{Height}
+dominoes in the grid: if this number is odd then one square will be blank.
+
+\lcont{
+
+(Grids with at least one odd dimension tend to be easier to solve.)
+
+}
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle. At Tricky level,
+you are required to make more deductions about empty dominoes and
+row/column counts. 
+
+\dt \e{Strip clues}
+
+\dd If true, some of the clues around the grid are removed at generation
+time, making the puzzle more difficult.
+
+
+\C{signpost} \i{Signpost}
+
+\cfg{winhelp-topic}{games.signpost}
+
+You have a grid of squares; each square (except the last one)
+contains an arrow, and some squares also contain numbers. Your job
+is to connect the squares to form a continuous list of numbers
+starting at 1 and linked in the direction of the arrows \dash so the
+arrow inside the square with the number 1 will point to the square
+containing the number 2, which will point to the square containing
+the number 3, etc. Each square can be any distance away from the
+previous one, as long as it is somewhere in the direction of the
+arrow.
+
+By convention the first and last numbers are shown; one or more
+interim numbers may also appear at the beginning. 
+
+Credit for this puzzle goes to \i{Janko} \k{janko-arrowpath}, who call it
+\q{Pfeilpfad} (\q{arrow path}).
+
+Signpost was contributed to this collection by James Harvey.
+
+\B{janko-arrowpath}
+\W{http://janko.at/Raetsel/Pfeilpfad/index.htm}\cw{http://janko.at/Raetsel/Pfeilpfad/index.htm}
+
+\H{signpost-controls} \I{controls, for Signpost}Signpost controls
+
+To play Signpost, you connect squares together by dragging from one
+square to another, indicating that they are adjacent in the
+sequence. Drag with the left button from a square to its successor,
+or with the right button from a square to its predecessor.
+
+If you connect together two squares in this way and one of them has
+a number in it, the appropriate number will appear in the other
+square. If you connect two non-numbered squares, they will be
+assigned temporary algebraic labels: on the first occasion, they
+will be labelled \cq{a} and \cq{a+1}, and then \cq{b} and \cq{b+1},
+and so on. Connecting more squares on to the ends of such a chain
+will cause them all to be labelled with the same letter.
+
+When you left-click or right-click in a square, the legal squares to
+connect it to will be shown.
+
+The arrow in each square starts off black, and goes grey once you
+connect the square to its successor. Also, each square which needs a
+predecessor has a small dot in the bottom left corner, which
+vanishes once you link a square to it. So your aim is always to
+connect a square with a black arrow to a square with a dot.
+
+To remove any links for a particular square (both incoming and
+outgoing), left-drag it off the grid. To remove a whole chain,
+right-drag any square in the chain off the grid.
+
+You can also use the cursor keys to move around the grid squares and
+lines. Pressing the return key when over a square starts a link
+operation, and pressing the return key again over a square will
+finish the link, if allowable. Pressing the space bar over a square
+will show the other squares pointing to it, and allow you to form a
+backward link, and pressing the space bar again cancels this.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{signpost-parameters} \I{parameters, for Signpost}Signpost parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Force start/end to corners}
+
+\dd If true, the start and end squares are always placed in opposite corners
+(the start at the top left, and the end at the bottom right). If false the start
+and end squares are placed randomly (although always both shown). 
+
+\C{range} \i{Range}
+
+\cfg{winhelp-topic}{games.range}
+
+You have a grid of squares; some squares contain numbers.  Your job is
+to colour some of the squares black, such that several criteria are
+satisfied:
+
+\b no square with a number is coloured black.
+
+\b no two black squares are adjacent (horizontally or vertically).
+
+\b for any two white squares, there is a path between them using only
+white squares.
+
+\b for each square with a number, that number denotes the total number
+of white squares reachable from that square going in a straight line
+in any horizontal or vertical direction until hitting a wall or a
+black square; the square with the number is included in the total
+(once).
+
+For instance, a square containing the number one must have four black
+squares as its neighbours by the last criterion; but then it's
+impossible for it to be connected to any outside white square, which
+violates the second to last criterion.  So no square will contain the
+number one.
+
+Credit for this puzzle goes to \i{Nikoli}, who have variously called
+it \q{Kurodoko}, \q{Kuromasu} or \q{Where is Black Cells}.
+\k{nikoli-range}.
+
+Range was contributed to this collection by Jonas K\u00F6{oe}lker.
+
+\B{nikoli-range}
+\W{http://www.nikoli.co.jp/en/puzzles/where_is_black_cells.html}\cw{http://www.nikoli.co.jp/en/puzzles/where_is_black_cells.html}
+
+\H{range-controls} \I{controls, for Range}Range controls
+
+Click with the left button to paint a square black, or with the right
+button to mark a square with a dot to indicate that you are sure it
+should \e{not} be painted black. Repeated clicking with either button
+will cycle the square through the three possible states (filled,
+dotted or empty) in opposite directions.
+
+You can also use the cursor keys to move around the grid squares.
+Pressing Return does the same as clicking with the left button, while
+pressing Space does the same as a right button click.  Moving with the
+cursor keys while holding Shift will place dots in all squares that
+are moved through.
+
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{range-parameters} \I{parameters, for Range}Range parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\C{pearl} \i{Pearl}
+
+\cfg{winhelp-topic}{games.pearl}
+
+You have a grid of squares. Your job is to draw lines between the
+centres of horizontally or vertically adjacent squares, so that the
+lines form a single closed loop. In the resulting grid, some of the
+squares that the loop passes through will contain corners, and some
+will be straight horizontal or vertical lines. (And some squares can
+be completely empty \dash the loop doesn't have to pass through every
+square.)
+
+Some of the squares contain black and white circles, which are clues
+that the loop must satisfy.
+
+A black circle in a square indicates that that square is a corner, but
+neither of the squares adjacent to it in the loop is also a corner.
+
+A white circle indicates that the square is a straight edge, but \e{at
+least one} of the squares adjacent to it in the loop is a corner.
+
+(In both cases, the clue only constrains the two squares adjacent
+\e{in the loop}, that is, the squares that the loop passes into after
+leaving the clue square. The squares that are only adjacent \e{in the
+grid} are not constrained.)
+
+Credit for this puzzle goes to \i{Nikoli}, who call it \q{Masyu}.
+\k{nikoli-pearl}
+
+Thanks to James Harvey for assistance with the implementation.
+
+\B{nikoli-pearl}
+\W{http://www.nikoli.co.jp/en/puzzles/masyu.html}\cw{http://www.nikoli.co.jp/en/puzzles/masyu.html}
+(beware of Flash)
+
+\H{pearl-controls} \I{controls, for Pearl}Pearl controls
+
+Click with the left button on a grid edge to draw a segment of the
+loop through that edge, or to remove a segment once it is drawn.
+
+Drag with the left button through a series of squares to draw more
+than one segment of the loop in one go. Alternatively, drag over an
+existing part of the loop to undraw it, or to undraw part of it and
+then go in a different direction.
+
+Click with the right button on a grid edge to mark it with a cross,
+indicating that you are sure the loop does not go through that edge.
+(For instance, if you have decided which of the squares adjacent to a
+white clue has to be a corner, but don't yet know which way the corner
+turns, you might mark the one way it \e{can't} go with a cross.)
+
+Alternatively, use the cursor keys to move the cursor.  Use the Enter
+key to begin and end keyboard \q{drag} operations.  Use the Space,
+Escape or Backspace keys to cancel the drag.  Or, hold Control while
+dragging with the cursor keys to toggle segments as you move between
+squares.
+
+Pressing Control-Shift-arrowkey or Shift-arrowkey simulates a left or
+right click, respectively, on the edge in the direction of the key.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{pearl-parameters} \I{parameters, for Pearl}Pearl parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\C{undead} \i{Undead}
+
+\cfg{winhelp-topic}{games.undead}
+
+You are given a grid of squares, some of which contain diagonal
+mirrors. Every square which is not a mirror must be filled with one of
+three types of undead monster: a ghost, a vampire, or a zombie.
+
+Vampires can be seen directly, but are invisible when reflected in
+mirrors. Ghosts are the opposite way round: they can be seen in
+mirrors, but are invisible when looked at directly. Zombies are
+visible by any means.
+
+You are also told the total number of each type of monster in the
+grid. Also around the edge of the grid are written numbers, which
+indicate how many monsters can be seen if you look into the grid along
+a row or column starting from that position. (The diagonal mirrors are
+reflective on both sides. If your reflected line of sight crosses the
+same monster more than once, the number will count it each time it is
+visible, not just once.)
+
+This puzzle type was invented by David Millar, under the name
+\q{Haunted Mirror Maze}. See \k{janko-undead} for more details.
+
+Undead was contributed to this collection by Steffen Bauer.
+
+\B{janko-undead}
+\W{http://www.janko.at/Raetsel/Spukschloss/index.htm}\cw{http://www.janko.at/Raetsel/Spukschloss/index.htm}
+
+\H{undead-controls} \I{controls, for Undead}Undead controls
+
+Undead has a similar control system to Solo, Unequal and Keen.
+
+To play Undead, click the mouse in any empty square and then type a
+letter on the keyboard indicating the type of monster: \q{G} for a
+ghost, \q{V} for a vampire, or \q{Z} for a zombie. If you make a
+mistake, click the mouse in the incorrect square and press Space to
+clear it again (or use the Undo feature).
+
+If you \e{right}-click in a square and then type a letter, the
+corresponding monster will be shown in reduced size in that square, as
+a \q{pencil mark}. You can have pencil marks for multiple monsters in
+the same square. A square containing a full-size monster cannot also
+contain pencil marks.
+
+The game pays no attention to pencil marks, so exactly what you use
+them for is up to you: you can use them as reminders that a particular
+square needs to be re-examined once you know more about a particular
+monster, or you can use them as lists of the possible monster in a
+given square, or anything else you feel like.
+
+To erase a single pencil mark, right-click in the square and type
+the same letter again.
+
+All pencil marks in a square are erased when you left-click and type a
+monster letter, or when you left-click and press Space. Right-clicking
+and pressing space will also erase pencil marks.
+
+As for Solo, the cursor keys can be used in conjunction with the letter
+keys to place monsters or pencil marks. Use the cursor keys to move a
+highlight around the grid, and type a monster letter to enter it in
+the highlighted square. Pressing return toggles the highlight into a
+mode in which you can enter or remove pencil marks.
+
+If you prefer plain letters of the alphabet to cute monster pictures,
+you can press \q{A} to toggle between showing the monsters as monsters or
+showing them as letters.
+
+Left-clicking a clue will mark it as done (grey it out), or unmark it
+if it is already marked.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{undead-parameters} \I{parameters, for Undead}Undead parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle.
+
+\C{unruly} \i{Unruly}
+
+\cfg{winhelp-topic}{games.unruly}
+
+You are given a grid of squares, which you must colour either black or
+white. Some squares are provided as clues; the rest are left for you
+to fill in. Each row and column must contain the same number of black
+and white squares, and no row or column may contain three consecutive
+squares of the same colour.
+
+This puzzle type was invented by Adolfo Zanellati, under the name
+\q{Tohu wa Vohu}. See \k{janko-unruly} for more details.
+
+Unruly was contributed to this collection by Lennard Sprong.
+
+\B{janko-unruly}
+\W{http://www.janko.at/Raetsel/Tohu-Wa-Vohu/index.htm}\cw{http://www.janko.at/Raetsel/Tohu-Wa-Vohu/index.htm}
+
+\H{unruly-controls} \I{controls, for Unruly}Unruly controls
+
+To play Unruly, click the mouse in a square to change its colour.
+Left-clicking an empty square will turn it black, and right-clicking
+will turn it white. Keep clicking the same button to cycle through the
+three possible states for the square. If you middle-click in a square
+it will be reset to empty.
+
+You can also use the cursor keys to move around the grid. Pressing the
+return or space keys will turn an empty square black or white
+respectively (and then cycle the colours in the same way as the mouse
+buttons), and pressing Backspace will reset a square to empty.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{unruly-parameters} \I{parameters, for Unruly}Unruly parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares. (Note that the rules of the game require
+both the width and height to be even numbers.)
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle.
+
+\dt \e{Unique rows and columns}
+
+\dd If enabled, no two rows are permitted to have exactly the same
+pattern, and likewise columns. (A row and a column can match, though.)
+
+\C{flood} \i{Flood}
+
+\cfg{winhelp-topic}{games.flood}
+
+You are given a grid of squares, coloured at random in multiple
+colours. In each move, you can flood-fill the top left square in a
+colour of your choice (i.e. every square reachable from the starting
+square by an orthogonally connected path of squares all the same
+colour will be filled in the new colour). As you do this, more and
+more of the grid becomes connected to the starting square.
+
+Your aim is to make the whole grid the same colour, in as few moves as
+possible. The game will set a limit on the number of moves, based on
+running its own internal solver. You win if you can make the whole
+grid the same colour in that many moves or fewer.
+
+I saw this game (with a fixed grid size, fixed number of colours, and
+fixed move limit) at http://floodit.appspot.com (no longer accessible).
+
+\H{flood-controls} \I{controls, for Flood}Flood controls
+
+To play Flood, click the mouse in a square. The top left corner and
+everything connected to it will be flood-filled with the colour of the
+square you clicked. Clicking a square the same colour as the top left
+corner has no effect, and therefore does not count as a move.
+
+You can also use the cursor keys to move a cursor (outline black
+square) around the grid. Pressing the return key will fill the top
+left corner in the colour of the square under the cursor.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{flood-parameters} \I{parameters, for Flood}Flood parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of the grid, in squares.
+
+\dt \e{Colours}
+
+\dd Number of colours used to fill the grid. Must be at least 3 (with
+two colours there would only be one legal move at any stage, hence no
+choice to make at all), and at most 10.
+
+\dt \e{Extra moves permitted}
+
+\dd Controls the difficulty of the puzzle, by increasing the move
+limit. In each new grid, Flood will run an internal solver to generate
+its own solution, and then the value in this field will be added to
+the length of Flood's solution to generate the game's move limit. So a
+value of 0 requires you to be just as efficient as Flood's automated
+solver, and a larger value makes it easier.
+
+\lcont{
+
+(Note that Flood's internal solver will not necessarily find the
+shortest possible solution, though I believe it's pretty close. For a
+real challenge, set this value to 0 and then try to solve a grid in
+\e{strictly fewer} moves than the limit you're given!)
+
+}
+
+\C{tracks} \i{Tracks}
+
+\cfg{winhelp-topic}{games.tracks}
+
+You are given a grid of squares, some of which are filled with train
+tracks. You need to complete the track from A to B so that the rows and
+columns contain the same number of track segments as are indicated in the
+clues to the top and right of the grid.
+
+There are only straight and 90 degree curved rails, and the track may not
+cross itself.
+
+Tracks was contributed to this collection by James Harvey.
+
+\H{tracks-controls} \I{controls, for Tracks}Tracks controls
+
+Left-clicking on an edge between two squares adds a track segment between
+the two squares. Right-clicking on an edge adds a cross on the edge,
+indicating no track is possible there.
+
+Left-clicking in a square adds a colour indicator showing that you know the
+square must contain a track, even if you don't know which edges it crosses
+yet. Right-clicking in a square adds a cross indicating it contains no
+track segment.
+
+Left- or right-dragging between squares allows you to lay a straight line
+of is-track or is-not-track indicators, useful for filling in rows or
+columns to match the clue.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{tracks-parameters} \I{parameters, for Tracks}Tracks parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of the grid, in squares.
+
+\dt \e{Difficulty}
+
+\dd Controls the difficulty of the generated puzzle: at Tricky level,
+you are required to make more deductions regarding disregarding moves
+that would lead to impossible crossings later.
+
+\dt \e{Disallow consecutive 1 clues}
+
+\dd Controls whether the Tracks game generation permits two adjacent
+rows or columns to have a 1 clue, or permits the row or column of the
+track's endpoint to have a 1 clue. By default this is not permitted,
+to avoid long straight boring segments of track and make the games
+more twiddly and interesting. If you want to restore the possibility,
+turn this option off.
+
+
+\C{palisade} \i{Palisade}
+
+\cfg{winhelp-topic}{games.palisade}
+
+You're given a grid of squares, some of which contain numbers.  Your
+goal is to subdivide the grid into contiguous regions, all of the same
+(given) size, such that each square containing a number is adjacent to
+exactly that many edges (including those between the inside and the
+outside of the grid).
+
+Credit for this puzzle goes to \i{Nikoli}, who call it \q{Five Cells}.
+\k{nikoli-palisade}.
+
+Palisade was contributed to this collection by Jonas K\u00F6{oe}lker.
+
+\B{nikoli-palisade}
+\W{http://nikoli.co.jp/en/puzzles/five_cells.html}\cw{http://nikoli.co.jp/en/puzzles/five_cells.html}
+
+\H{palisade-controls} \I{controls, for Palisade}Palisade controls
+
+Left-click to place an edge.  Right-click to indicate \q{no edge}.
+Alternatively, the arrow keys will move a keyboard cursor.  Holding
+Control while pressing an arrow key will place an edge.  Press
+Shift-arrowkey to switch off an edge.  Repeat an action to perform
+its inverse.
+
+(All the actions described in \k{common-actions} are also available.)
+
+\H{Palisade-parameters} \I{parameters, for Palisade}Palisade parameters
+
+These parameters are available from the \q{Custom...} option on the
+\q{Type} menu.
+
+\dt \e{Width}, \e{Height}
+
+\dd Size of grid in squares.
+
+\dt \e{Region size}
+
+\dd The size of the regions into which the grid must be subdivided.
+
+\A{licence} \I{MIT licence}\ii{Licence}
+
+This software is \i{copyright} 2004-2014 Simon Tatham.
+
+Portions copyright Richard Boulton, James Harvey, Mike Pinna, Jonas
+K\u00F6{oe}lker, Dariusz Olszewski, Michael Schierl, Lambros Lambrou,
+Bernd Schmidt, Steffen Bauer, Lennard Sprong and Rogier Goossens.
+
+Permission is hereby granted, free of charge, to any person
+obtaining a copy of this software and associated documentation files
+(the \q{Software}), to deal in the Software without restriction,
+including without limitation the rights to use, copy, modify, merge,
+publish, distribute, sublicense, and/or sell copies of the Software,
+and to permit persons to whom the Software is furnished to do so,
+subject to the following conditions:
+
+The above copyright notice and this permission notice shall be
+included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED \q{AS IS}, WITHOUT WARRANTY OF ANY KIND,
+EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+
+\IM{command-line}{command line} command line
+
+\IM{default parameters, specifying} default parameters, specifying
+\IM{default parameters, specifying} preferences, specifying default
+
+\IM{Unix} Unix
+\IM{Unix} Linux
+
+\IM{generating game IDs} generating game IDs
+\IM{generating game IDs} game ID, generating
+
+\IM{specific} \q{Specific}, menu option
+\IM{custom} \q{Custom}, menu option
+
+\IM{game ID} game ID
+\IM{game ID} ID, game
+\IM{ID format} ID format
+\IM{ID format} format, ID
+\IM{ID format} game ID, format
+
+\IM{keys} keys
+\IM{keys} shortcuts (keyboard)
+
+\IM{initial state} initial state
+\IM{initial state} state, initial
+
+\IM{MIT licence} MIT licence
+\IM{MIT licence} licence, MIT