\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 2004-2008 Simon Tatham. All rights
+\copyright This manual is copyright 2004-2012 Simon Tatham. All rights
reserved. You may distribute this documentation under the MIT licence.
See \k{licence} for the licence text in full.
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 - it's hard to think of a sensible printable representation
+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{_})
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{cube o2x2}.
+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
For example:
-\c net --generate 12 --print 2x3 7x7w | lpr
+\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}
For example:
-\c net --generate 12 --save game --save-suffix .sav
+\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}.
\H{sixteen-controls} \I{controls, for Sixteen}Sixteen controls
-This game is played with the mouse. 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.
+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.
(All the actions described in \k{common-actions} are also available.)
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
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.
-See \k{sixteen-controls}.
+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
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.
+
(All the actions described in \k{common-actions} are also available.)
\H{pattern-parameters} \I{parameters, for Pattern}Pattern parameters
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}.
+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
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.
+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
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
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
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
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.
+
(All the actions described in \k{common-actions} are also available.)
\H{dominosa-parameters} \I{parameters, for Dominosa}Dominosa parameters
\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 from positions
-on the edge of the arena and observing how they are deflected.
+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.
-Lasers will fire straight until they hit the opposite side of the
-arena (at which point they emerge), unless affected by balls in one of
-the following ways:
+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 laser that hits a ball head-on is absorbed and will never re-emerge.
- This includes lasers that meet a ball on the first rank of the arena.
+\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 laser with a ball to its front-left square gets deflected 90 degrees
+\b A beam with a ball to its front-left square gets deflected 90 degrees
to the right.
-\b A laser with a ball to its front-right square gets similarly deflected
+\b A beam with a ball to its front-right square gets similarly deflected
to the left.
-\b A laser that would re-emerge from the entry location is considered to be
+\b A beam that would re-emerge from its entry location is considered to be
\q{reflected}.
-\b A laser which would get deflected before entering the arena (down the
- \q{firing range}) by a ball to the front-left or front-right of its
- entry point is also 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}.
-Lasers that are reflected appear as a \q{R}; lasers that hit balls
-dead-on appear as \q{H}. Otherwise, a number appears at the firing point
-and the location where the laser emerges (this number is unique to
-that shot).
+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 lasers; once you have placed enough
+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 laser behaviours shown above:
+of the beam behaviours shown above:
\c 1RHR----
\c |..O.O...|
\c |.....O..|
\c 12-RH---
-As shown, it is possible for a ball to receive multiple reflections
-before re-emerging (see turn 3). Similarly, a ball may be reflected
+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 that 4 balls may have a non-unique
+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 x):
+ball is (possible positions marked with an \cw{x}):
\c --------
\c |........|
\c |........|
\c --------
-For this reason when you have your guesses checked the game will
+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 x, and you would still win.
+\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} 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, left-click in a square around the side of the arena.
-The results will be displayed immediately. Lasers may not be fired
-twice (because the results will never change). Holding down the left
-button will highlight the current go (or a previous go) to confirm the
-exit point for that laser, if applicable.
+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; to remove the guessed ball
-click again.
+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 firing range above/below that column, or
-to the left/right of that row.
+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 will mark
-your guesses.
+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{mark} button and your guesses are not correct,
-the game will show you as little information as possible to
+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 laser paths you already know
-about, one laser path will be circled to indicate that it proves you
-wrong. If your positions match all the existing laser paths but are
-still wrong, one new laser path will be revealed (written in red)
+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
-are displayed as filled black circles with red crosses, and missing
-balls are 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 mark button), and red text marks
-any laser you \e{could} have fired in order to distinguish your ball
-layout from the right one.
+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.)
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 laser inputs and outputs match.
+if all the beam inputs and outputs match.
\C{slant} \i{Slant}
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
\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 differnt types of face (e.g.
+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.
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. Pressing the
+return key followed by a cursor key will lay a bridge in that direction
+(if available); pressing the space bar followed by a cursor key will
+lay a \q{non-bridge} marker.
+
+You can mark an island as finished by pressing the return key twice.
+
Violations of the puzzle rules will be marked in red:
\b An island with too many bridges will be highlighted in red.
\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 greater-than signs between
+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 greater-than signs are satisfied.
+\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{Trivial} mode (available via the \q{Custom} game type
-selector), there are no greater-than signs; the puzzle is to solve
-the \i{Latin square} only.
+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.
-At the time of writing, this puzzle is appearing in the Guardian
-weekly under the name \q{\i{Futoshiki}}.
+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.
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.
+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
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 'M' key to
-auto-fill every numeric hint, ready for removal as required.
+auto-fill every numeric hint, ready for removal as required, or the '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.
(All the actions described in \k{common-actions} are also available.)
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.
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 nest time the return key is
+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.
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.
+
+
+\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.
+
+(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/index.html}\cw{http://www.nikoli.com/en/puzzles/hitori/index.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.
+
+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.
+
+(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 number of
+squares reachable from that square going in each direction until
+hitting a wall or a black square.
+
+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/}\cw{http://www.nikoli.co.jp/en/puzzles/where_is_black_cells/}
+
+\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.
+
+(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/}\cw{http://www.nikoli.co.jp/en/puzzles/masyu/}
+
+\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 `drag' operations. Use the Space key to
+cancel the drag. Use Ctrl-arrowkey and Shift-arrowkey to simulate a
+left or right click, respectively, on the edge in the given direction
+relative to the cursor, i.e. to draw a segment or a cross.
+
+(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.
+
+(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.
\A{licence} \I{MIT licence}\ii{Licence}
-This software is \i{copyright} 2004-2008 Simon Tatham.
+This software is \i{copyright} 2004-2012 Simon Tatham.
Portions copyright Richard Boulton, James Harvey, Mike Pinna, Jonas
-K\u00F6{oe}lker, Dariusz Olszewski, Michael Schierl and Lambros
-Lambrou.
+K\u00F6{oe}lker, Dariusz Olszewski, Michael Schierl, Lambros
+Lambrou, Bernd Schmidt, Steffen Bauer and Lennard Sprong.
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation files
~mdw / sgt / puzzles / blobdiff