sudokuDLX is a go package for solving sudoku puzzles using Donald Knuth's dancing links agorithm. It accepts sudokus of varying dimensions in the form of a square 2D int slice along with the x and y dimesnions of a single block in the provied sudoku.
A sudoku can be solved using the method: Solve(puzzle [][]int, blockXDim, blockYDim int) ([][]int , bool) which will return the solution and a boolean indicator of success.
The dashes, vertical lines, and plus cells below are not part of the int slice, but included for the sake of visualizaton.
To solve a standard sudoku stored in a variable named puzzle:
| 3 | | | 8 | | | |||||||
| | | 7 | | | 5 | |||||||
| 1 | | | | | ||||||||
| - | - | - | + | - | - | - | + | - | - | - |
| | | | | 3 | 6 | |||||||
| 2 | | | 4 | | | |||||||
| 7 | | | | | ||||||||
| - | - | - | + | - | - | - | + | - | - | - |
| | | 6 | | | 1 | 3 | ||||||
| 4 | 5 | | | 2 | | | ||||||
| | | | | 8 |
solution, success := sudokuDlx.Solve(puzzle, 3, 3)
Which will return success = true with the solution:
| 3 | 5 | 4 | | | 1 | 8 | 6 | | | 9 | 2 | 7 |
| 2 | 9 | 8 | | | 7 | 4 | 3 | | | 6 | 1 | 5 |
| 1 | 6 | 7 | | | 9 | 5 | 2 | | | 4 | 8 | 3 |
| - | - | - | + | - | - | - | + | - | - | - |
| 9 | 3 | 2 | | | 6 | 1 | 4 | | | 5 | 7 | 8 |
| 4 | 8 | 1 | | | 5 | 2 | 7 | | | 3 | 6 | 9 |
| 5 | 7 | 6 | | | 3 | 9 | 8 | | | 2 | 4 | 1 |
| - | - | - | + | - | - | - | + | - | - | - |
| 7 | 2 | 9 | | | 8 | 6 | 5 | | | 1 | 3 | 4 |
| 8 | 4 | 5 | | | 2 | 3 | 1 | | | 7 | 9 | 6 |
To solve a non standard dimension sudoku like this 7x2 puzzle:
| 1 | 2 | 10 | 7 | | | 11 | |||||||||
| 12 | 6 | | | 10 | 4 | 2 | |||||||||
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 4 | 10 | 12 | 13 | | | 14 | 11 | 1 | |||||||
| 11 | 6 | 1 | 7 | 14 | | | 12 | ||||||||
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 6 | 4 | | | 3 | |||||||||||
| 3 | 10 | 13 | 8 | 1 | 2 | | | 9 | 6 | ||||||
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 7 | 10 | 4 | 13 | | | 5 | 11 | 8 | 12 | ||||||
| 11 | 8 | 14 | 9 | | | 3 | 2 | 10 | 4 | ||||||
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 14 | 11 | | | 7 | 1 | 6 | 2 | 10 | 13 | ||||||
| 6 | | | 5 | 12 | |||||||||||
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 14 | | | 13 | 8 | 12 | 11 | 5 | ||||||||
| 5 | 7 | 12 | | | 9 | 1 | 14 | 6 | |||||||
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 13 | 7 | 12 | | | 6 | 2 | |||||||||
| 14 | | | 12 | 3 | 7 | 8 |
solution, success := sudokuDlx.Solve(puzzle, 3, 3)
Which will return success = true with the solution:
| 13 | 1 | 14 | 4 | 2 | 10 | 7 | | | 8 | 6 | 3 | 12 | 5 | 9 | 11 |
| 12 | 5 | 11 | 9 | 3 | 8 | 6 | | | 10 | 13 | 14 | 4 | 2 | 7 | 1 |
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 4 | 10 | 3 | 12 | 13 | 2 | 8 | | | 9 | 14 | 11 | 6 | 1 | 5 | 7 |
| 11 | 6 | 9 | 5 | 1 | 7 | 14 | | | 4 | 12 | 10 | 3 | 13 | 2 | 8 |
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 9 | 12 | 6 | 11 | 14 | 5 | 4 | | | 1 | 2 | 13 | 8 | 8 | 10 | 3 |
| 7 | 3 | 10 | 13 | 8 | 1 | 2 | | | 11 | 9 | 4 | 5 | 14 | 6 | 12 |
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 3 | 7 | 2 | 10 | 4 | 6 | 13 | | | 14 | 5 | 1 | 11 | 8 | 12 | 9 |
| 1 | 11 | 8 | 14 | 12 | 9 | 5 | | | 3 | 7 | 2 | 10 | 6 | 4 | 13 |
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 5 | 14 | 12 | 8 | 9 | 11 | 3 | | | 7 | 1 | 6 | 2 | 10 | 13 | 4 |
| 6 | 4 | 7 | 2 | 10 | 13 | 1 | | | 5 | 11 | 8 | 9 | 12 | 3 | 14 |
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 2 | 9 | 4 | 1 | 6 | 14 | 10 | | | 13 | 8 | 12 | 7 | 3 | 11 | 5 |
| 8 | 13 | 5 | 3 | 7 | 12 | 11 | | | 2 | 10 | 9 | 1 | 4 | 14 | 6 |
| -- | -- | -- | -- | -- | -- | -- | + | -- | -- | -- | -- | -- | -- | -- |
| 10 | 8 | 13 | 7 | 11 | 3 | 12 | | | 6 | 4 | 5 | 14 | 9 | 1 | 2 |
| 14 | 2 | 1 | 6 | 5 | 4 | 9 | | | 12 | 3 | 7 | 13 | 11 | 8 | 10 |