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* Kitty - greedy backtracking-based sudoku solver                             *
* Copyright (C) 2008  Olexandr Melnyk <[email protected]>                        *
*                                                                             *
* This program is free software: you can redistribute it and/or modify        *
* it under the terms of the GNU General Public License as published by        *
* the Free Software Foundation, either version 3 of the License, or           *
* (at your option) any later version.                                         *
*                                                                             *
* This program is distributed in the hope that it will be useful,             *
* but WITHOUT ANY WARRANTY; without even the implied warranty of              *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               *
* GNU General Public License for more details.                                *
*                                                                             *
* You should have received a copy of the GNU General Public License           *
* along with this program.  If not, see <http://www.gnu.org/licenses/>.       *
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=== 1. INSTALLATION ===

In order to install Kitty, you can use the traditional chain of commands on UNIX-like operating systems:

./configure
make
make install

=== 2. USAGE ===

Kitty package consists of two command-line utilities: kitty and meow. First one is a tool for solving sudoku puzzles and second one is a tool for verification that solution is correct.

Both kitty and meow use straight-forward puzzle format for input/output, where zeroes stand for empty cells (they can appear only in input, but not output) and numbers from 1 to 9 stand for themselves, eg.:

1 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
2 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0

To solve a puzzle, you can save it in a file input.txt, and then call kitty as follows:

kitty < input.txt > output.txt

If puzzle has a solution, it will be stored in output.txt, else it output.txt will contain "No solution".

To verify that grid stored in file output.txt is a solution of puzzle stored in file input.txt, you can use meow as follows:

cat input.txt output.txt | meow

== 3. WEB SITE ==

You can visit Kitty web site at http://omelnyk.net/projects/kitty/