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

Solving Technique Example

Original sudoku:

....5..8...7.293..1...74..25.91.2..4....4.........816.718....2...........6......7

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

:0701:3:...+35+1+78.+8+57+6293+4+11..+874..25.91+62+8.4+6+8+1.4.+2.......816.718....2.....+1...+8.6..+8..+17::361 362 363:

The following representation can be pasted in most Sudoku programs:

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

| 249   249   246  | 3      5   1    | 7     8     69   |

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

| 1     39    36   | 8      7   4    | 569   59    2    |

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

| 5     37    9    | 1      6   2    | 8     37    4    |

| 6     8     1    | 579    4   357  | 2     3579  359  |

| 234   2347  234  | 579    39  8    | 1     6     359  |

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

| 7     1     8    | 459    39  356  | 4569  2     3569 |

| 2349  2349  2345 | 24579  1   3567 | 4569  359   8    |

| 2349  6     2345 | 2459   8   35   | 459   1     7    |

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

Representation of the step:

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

| 249    249    246  | 3       5   1    | 7      8      69   |

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

| 1      39     36   | 8       7   4    | 569    59     2    |

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

| 5     *37     9    | 1       6   2    | 8     *37     4    |

| 6      8      1    | 579     4   357  | 2      3579   359  |

| 2-34   2-347  2-34 | 579    *39  8    | 1      6      359  |

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

| 7      1      8    | 459    *39  356  | 4569   2     *3569 |

| 2349   2349   2345 | 24579   1   3567 | 4569  *359    8    |

| 2349   6      2345 | 2459    8   35   | 459    1      7    |

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



X-Chain: 3 r4c2 =3= r4c8 -3- r8c8 =3= r7c9 -3- r7c5 =3= r6c5 => r6c123<>3