I Love Sudoku

I Love Sudoku is a gem for solving any sudoku puzzle. Documentation for public methods is below. You can also read about how it works at this link.

Add this line to your application's Gemfile:

gem 'i_love_sudoku'

And then execute:

$ bundle

Or install it yourself as:

$ gem install i_love_sudoku

###ILoveSudoku.new(matrix)

You can create a new puzzle either with or without a ready-made matrix.

If you have a 9x9 nested array already, for example if you're using the gem in the context of a web app where that formatted object comes over from the front end, you can create a new puzzle with that array. Note that empty spaces are represented by nil.

$ matrix = [ [nil, 7, nil, nil, nil, nil, 5, nil, nil],
             [nil, nil, nil, nil, 5, 1, nil, nil, nil],
             [nil, nil, nil, 3, 7, 9, 2, 6, 8],
             [1, 2, nil, nil, 8, nil, 4, nil, 6],
             [nil, 4, nil, nil, nil, nil, nil, 9, nil],
             [9, nil, 3, nil, 2, nil, nil, 8, 5],
             [8, 9, 7, 2, 4, 3, nil, nil, nil],
             [nil, nil, nil, 6, 1, nil, nil, nil, nil],
             [nil, nil, 2, nil, nil, nil, nil, 4, nil] ]
$ puzzle = ILoveSudoku.new(matrix)
$ puts puzzle.unsolved_string
.7.|...|5..
...|.51|...
...|379|268
---+---+---
12.|.8.|4.6
.4.|...|.9.
9.3|.2.|.85
---+---+---
897|243|...
...|61.|...
..2|...|.4.

If you're playing with the gem in your terminal, it probably makes more sense to create a puzzle with no matrix and manually input the separate lines. See #edit_row for details.

$ puzzle = ILoveSudoku.new
$ puts puzzle.unsolved_string
...|...|...
...|...|...
...|...|...
---+---+---
...|...|...
...|...|...
...|...|...
---+---+---
...|...|...
...|...|...
...|...|...

####edit_row(row_number, string) This method takes the row number (indexed from 0) and a string of periods and integers and overwrites the existing row. This is a good way to manually enter a puzzle in your command line.

$ puzzle = ILoveSudoku.new
$ puzzle.edit_row(1, "3..4..678")
$ puts puzzle.unsolved_string
...|...|...
3..|4..|678
...|...|...
---+---+---
...|...|...
...|...|...
...|...|...
---+---+---
...|...|...
...|...|...
...|...|...

####unsolved_string and #unsolved_matrix Returns the current state of the puzzle input in string or matrix format.

####solved_string and #solved_matrix Returns the solved puzzle in string or matrix format.

Bug reports and pull requests are welcome on GitHub at https://github.com/dsberger/i_love_sudoku.

The gem is available as open source under the terms of the MIT License.