HoDoKu Solving Technique Index: Example for "XY-Chain"

Solving Technique Example

Original sudoku:

.7.4..69...82...536................4....9.5..3.......12..367.........2.51.6..84..

Use the following line if you want to load the sudoku in HoDoKu:

:0702:8:+57.4.+169.+9+482+7+6+1536.....+7+4...+9...+3.4+4...9+35.+63.+5...+9.12+5+4367+8+1+9......2+651+96+5+284+3+7::815 835 844 854 864:

The following representation can be pasted in most Sudoku programs:

.---------------.---------------.------------.

| 5   7     23  | 4     38   1  | 6  9    28 |

| 9   4     8   | 2     7    6  | 1  5    3  |

| 6   123   123 | 89    358  59 | 7  4    28 |

:---------------+---------------+------------:

| 78  1268  9   | 1678  158  25 | 3  278  4  |

| 4   128   127 | 178   9    3  | 5  278  6  |

| 3   268   5   | 678   48   24 | 9  278  1  |

:---------------+---------------+------------:

| 2   5     4   | 3     6    7  | 8  1    9  |

| 78  38    37  | 19    14   49 | 2  6    5  |

| 1   9     6   | 5     2    8  | 4  3    7  |

'---------------'---------------'------------'

Representation of the step:

.---------------.-------------------.------------.

| 5   7     23  |  4       3-8   1  | 6  9    28 |

| 9   4     8   |  2       7     6  | 1  5    3  |

| 6   123   123 | *89      35-8  59 | 7  4    28 |

:---------------+-------------------+------------:

| 78  1268  9   |  167-8   158   25 | 3  278  4  |

| 4   128   127 |  17-8    9     3  | 5  278  6  |

| 3   268   5   |  67-8   *48    24 | 9  278  1  |

:---------------+-------------------+------------:

| 2   5     4   |  3       6     7  | 8  1    9  |

| 78  38    37  | *19     *14    49 | 2  6    5  |

| 1   9     6   |  5       2     8  | 4  3    7  |

'---------------'-------------------'------------'



XY-Chain 8- r6c5 -4- r8c5 -1- r8c4 -9- r3c4 -8 => r13c5,r456c4<>8