sudoku_bardi

Summary

Sudoku solver, validator and generator

Description

sudoku_bardi (see websudoku.com) is a set of tools for solving, validating and generating Sudoku puzzles.

Why should one the sudoku_bardi tools?

The Sudoku solution algorithm does not use recursion -- runs in limited memory and can find all solutions of incorrect puzzles.

Version

v0.1.0 with comprehensive tests, was developed using ruby 1.9.3 and rspec 2.13.0. It does not have any specific Sudoku puzzle generators yet; however it provides a good foundation for any generator as it provides validation of solution uniqueness and shows the operations used in the puzzle solution(s).

Installation

Get the v0.1.0 gem or clone the repository.

Usage and documentation

Study the programs in the spec/ directory. See below for more information.

Try the software in irb:

irb prompt> load 'lib/sudoku_bardi.rb'
irb prompt> load 'spec/support/sudoku_fixture.rb'
irb prompt> include SudokuBardi
irb prompt> include SudokuFixture
irb prompt> s = Solver.new EXAMPLE2
irb prompt> s.take 1

After -- s.take 1 -- one will see a listing of an array of size 2. The 0 element is an array of operations made to get the solution. The 1 element is the solution.

[75, SudokuBardi::Five] means assign Five to square 75.
["start"] ends the operations to construct the puzzle.
["mark", 2, [SudokuBardi::Seven, SudokuBardi::Two], 1]
  shows a backtrack mark for square 2. That type of thing
  occurs when there is no longer any square with only one
  possible value. The solver had to try Seven and Two to
  get all possible solutions. The 1 points at Two as the
  current value chosen.

  0  1  2  3  4  5  6  7  8
  9 10 11 12 13 14 15 16 17
 18 19 20 21 22 23 24 25 26
 27 28 29 30 31 32 33 34 35
 36 37 38 39 40 41 42 43 44
 45 46 47 48 49 50 51 52 53
 54 55 56 57 58 59 60 61 62
 63 64 65 66 67 68 69 70 71
 72 73 74 75 76 77 78 79 80

Requirements

Most likely any recent version of 1.9 ruby works.

Test with rspec ~> 2.11, rspec -fd