HoDoKu Solving Technique Index: Example for "Unique Rectangle Type 4"

Solving Technique Example

Original sudoku:

..9..7......6....3...5218...14..5..7.83...2...............8.64..6...3..17.......5

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

:0603:2:+8.9..7......6+9+8..3...5218..+214+8.5..7.83.+7.2..........+8...+78.64..6..+53+7.17.......5:312 412 417 419 223 127 128 638 639 958 959 367 967 968 971 272 972 273 292 392 193:288 298:

The following representation can be pasted in most Sudoku programs:

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

| 8    25    9   | 34     34    7    | 15   1256  26 |

| 145  2457  157 | 6      9     8    | 45   257   3  |

| 346  347   67  | 5      2     1    | 8    79    49 |

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

| 2    1     4   | 8      36    5    | 39   369   7  |

| 569  8     3   | 149    7     469  | 2    156   46 |

| 569  579   567 | 12349  1346  2469 | 145  1356  8  |

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

| 135  35    15  | 7      8     29   | 6    4     29 |

| 49   6     28  | 249    5     3    | 7    289   1  |

| 7    49    28  | 1249   146   2469 | 39   2389  5  |

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

Representation of the step:

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

| 8    25     9   | 34     34    7    | 15    1256   26 |

| 145  2457   157 | 6      9     8    | 45    257    3  |

| 346  347    67  | 5      2     1    | 8     79     49 |

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

| 2    1      4   | 8      36    5    | 39    369    7  |

| 569  8      3   | 149    7     469  | 2     156    46 |

| 569  579    567 | 12349  1346  2469 | 145   1356   8  |

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

| 135  35     15  | 7      8     29   | 6     4      29 |

| 49   6     *28  | 249    5     3    | 7    *-289   1  |

| 7    49    *28  | 1249   146   2469 | 39   *-2389  5  |

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



Uniqueness Test 4: 2/8 in r8c38,r9c38 => r89c8<>2