HoDoKu Solving Technique Index: Example for "Naked Quadruple"

Solving Technique Example

Original sudoku:

.3..8....9.8.41.....19..2.7.254..6....3.17.5.7......................51.6...3...98

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

:0202:469:+53+2+78+6...9+78+241.+6...19+5+32+87.254..6+7...3+617.5+27..+5........+1........+8.51.6...3...98::471 472 481 491 492 671 672 691 692 972:

The following representation can be pasted in most Sudoku programs:

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

| 5      3      2    | 7  8     6   | 49    14   149  |

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

| 46     46     1    | 9  5     3   | 2     8    7    |

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

| 18     2      5    | 4  39    89  | 6     7    139  |

| 48     489    3    | 6  1     7   | 489   5    2    |

| 7      14689  469  | 5  239   289 | 3489  134  1349 |

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

| 23468  45689  4679 | 1  2679  249 | 3457  234  345  |

| 234    49     479  | 8  279   5   | 1     234  6    |

| 1246   1456   467  | 3  267   24  | 457   9    8    |

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

Representation of the step:

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

| 5         3         2    | 7  8     6   | 49    14   149  |

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

| 46        46        1    | 9  5     3   | 2     8    7    |

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

| 18        2         5    | 4  39    89  | 6     7    139  |

| 48        489       3    | 6  1     7   | 489   5    2    |

| 7         14689     469  | 5  239   289 | 3489  134  1349 |

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

| 23-4-68  -45-68-9  *4679 | 1  2679  249 | 3457  234  345  |

| 23-4     *49       *479  | 8  279   5   | 1     234  6    |

| 12-4-6    1-45-6   *467  | 3  267   24  | 457   9    8    |

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



Naked Quadruple: 4,6,7,9 in r789c3,r8c2 => r7c12,r89c1,r9c2<>4, r7c12,r9c12<>6, r7c2<>9