+
+\C{solo} \i{Solo}
+
+\cfg{winhelp-topic}{games.solo}
+
+You have a square grid, which is divided into square or rectangular
+blocks. 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.
+
+You are given some of the numbers as clues; your aim is to place the
+rest of the numbers correctly.
+
+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).
+
+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}.
+
+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}.
+
+\B{nikoli-solo} \W{http://www.nikoli.co.jp/puzzles/1/index_text-e.htm}\cw{http://www.nikoli.co.jp/puzzles/1/index_text-e.htm}
+
+\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).
+
+(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.)
+
+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.
+
+\H{solo-cmdline} \I{command line, for Solo}Additional command-line
+configuration
+
+The symmetry parameter, described in \k{solo-parameters}, is not
+mentioned by default in the game ID (see \k{common-id}). So if you
+set your symmetry to (say) 4-way rotational, and then you generate a
+3\by\.4 grid, then the game ID will simply say \c{3x4:}\e{numbers}.
+This means that if you send the game ID to another player and they
+paste it into their copy of Solo, their game will not be
+automatically configured to use the same symmetry in any subsequent
+grids it generates. (I don't think the average person examining a
+single grid sent to them by another player would want their
+configuration modified to that extent.)
+
+If you are specifying a game ID or game parameters on the command
+line (see \k{common-cmdline}) and you do want to configure the
+symmetry, you can do it by suffixing additional text to the
+parameters:
+
+\b \cq{m4} for 4-way mirror symmetry
+
+\b \cq{r4} for 4-way rotational symmetry
+
+\b \cq{r2} for 2-way rotational symmetry
+
+\b \cq{a} for no symmetry at all (stands for \q{asymmetric})
+
+So, for example, you can make Solo generate asymmetric 3x4 grids by
+running \cq{solo 3x4a}, or 4-way rotationally symmetric 2x3 grids by
+running \cq{solo 2x3r4}.
+
+