HoDoKu Solving Technique Index: Example for "Alternate Inference Chain Type 2"

Solving Technique Example

Original sudoku:

.1.....2..78..95..4....8..739.1....6.......3...6...9.......3....3..8..9...16.2..5

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

:0708:48:+51+3...+82+9+678+2+195+4+34+2+9..8+1+6739.1.+5.+86.+5.....3...6...9+5..+6...3.+1+8.3..8+1+69...16.2+3+75::464 862:

The following representation can be pasted in most Sudoku programs:

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

| 5     1   3    | 47    467    467 | 8    2  9   |

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

| 4     2   9    | 35    35     8   | 1    6  7   |

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

| 3     9   247  | 1     247    5   | 247  8  6   |

| 1278  5   247  | 4789  24679  467 | 247  3  124 |

| 1278  48  6    | 3478  2347   47  | 9    5  124 |

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

| 279   6   2457 | 4579  4579   3   | 24   1  8   |

| 27    3   2457 | 457   8      1   | 6    9  24  |

| 89    48  1    | 6     49     2   | 3    7  5   |

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

Representation of the step:

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

| 5      1    3    |  47      467    467 | 8    2  9   |

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

| 4      2    9    |  35      35     8   | 1    6  7   |

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

| 3      9    247  |  1       247    5   | 247  8  6   |

| 1278   5    247  | *4789   *24679  467 | 247  3  124 |

| 1278  *4-8  6    | *3-478   2347   47  | 9    5  124 |

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

| 279    6    2457 |  4579    4579   3   | 24   1  8   |

| 27     3    2457 |  457     8      1   | 6    9  24  |

| 89    *48   1    |  6      *49     2   | 3    7  5   |

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



AIC 4- r6c2 =4= r9c2 -4- r9c5 -9- r5c5 =9= r5c4 =8= r6c4 -8 => r6c4<>4, r6c2<>8