HoDoKu Solving Technique Index: Example for "Hidden Quadruple"

Solving Technique Example

Original sudoku:

8..57.29.39..........2.......1...5.8...496......8.....2.9.....1..8....7.56.....82

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

:0212:36:8+1+657+329+439+2......+4+5+72.+9..+6+9+41...5+68+7+8+5496+1+2+3+6+2+38...+4.2+79.....1+1+38....7.56+4....82:766 377 987:375 675 685:

The following representation can be pasted in most Sudoku programs:

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

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

| 3  9  2 | 16    1468   148 | 78  15  57 |

| 4  5  7 | 2     18     9   | 38  13  6  |

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

| 9  4  1 | 37    23     27  | 5   6   8  |

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

| 6  2  3 | 8     15     15  | 79  4   79 |

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

| 2  7  9 | 36    34568  458 | 46  35  1  |

| 1  3  8 | 69    2456   245 | 46  7   59 |

| 5  6  4 | 1379  13     17  | 39  8   2  |

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

Representation of the step:

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

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

| 3  9  2 | 16     1468      148 | 78  15  57 |

| 4  5  7 | 2      18        9   | 38  13  6  |

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

| 9  4  1 | 37     23        27  | 5   6   8  |

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

| 6  2  3 | 8      15        15  | 79  4   79 |

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

| 2  7  9 | 36    *-345-68  *458 | 46  35  1  |

| 1  3  8 | 69    *245-6    *245 | 46  7   59 |

| 5  6  4 | 1379   13        17  | 39  8   2  |

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



Hidden Quadruple: 2,4,5,8 in r7c56,r8c56 => r7c5<>3, r78c5<>6