The Sudoku Validator library provides a mechanism for validating a Sudoku solution.
A valid Sudoku solution is one in which the number one through nine appears only once in each vertical row, horizontal row, and square.
The SudokuValidator class takes a multi-line string with a solved solution:
A valid solution:
4 3 5 | 2 6 9 | 7 8 1
6 8 2 | 5 7 1 | 4 9 3
1 9 7 | 8 3 4 | 5 6 2
------+------+------
8 2 6 | 1 9 5 | 3 4 7
3 7 4 | 6 8 2 | 9 1 5
9 5 1 | 7 4 3 | 6 2 8
------+------+------
5 1 9 | 3 2 6 | 8 7 4
2 4 8 | 9 5 7 | 1 3 6
7 6 3 | 4 1 8 | 2 5 9
An invalid solution (the number 3 appears multiple times in the horizontal, vertical, and square):
3 3 5 | 2 6 9 | 7 8 1
3 8 2 | 5 7 1 | 4 9 3
1 9 7 | 8 3 4 | 5 6 2
------+------+------
8 2 6 | 1 9 5 | 3 4 7
3 7 4 | 6 8 2 | 9 1 5
9 5 1 | 7 4 3 | 6 2 8
------+------+------
5 1 9 | 3 2 6 | 8 7 4
2 4 8 | 9 5 7 | 1 3 6
7 6 3 | 4 1 8 | 2 5 9
The SudokuValidator library is written in Ruby. The only development requirement is having Ruby 2.0 or greater available on your system.
Tests for the SudokuValidator are written using MiniTest, using the Spec style. Tests can run with:
$ ruby sudoku_validator_spec.rb