The New Sudoku Players' Forum

[blue]

There are "four in one" puzzles, like this ...

Code: Select all

+------------------+------------------+--------------+
| 1     4     3579 | 3579  6     2    | 8    379  57 |
| 2     3579  6    | 8     3579  3579 | 359  4    1  |
| 3579  3579  8    | 4     1     3579 | 6    379  2  |
+------------------+------------------+--------------+
| 3579  8     4    | 3579  3579  6    | 2    1    57 |
| 6     3579  2    | 1     3579  8    | 359  379  4  |
| 3579  1     3579 | 2     4     3579 | 359  6    8  |
+------------------+------------------+--------------+
| 8     579   579  | 6     579   4    | 1    2    3  |
| 379   2     1    | 379   8     379  | 4    5    6  |
| 4     6     35   | 35    2     1    | 7    8    9  |
+------------------+------------------+--------------+

14..628..2.68...41..841.6.2.84..621.6.21.8..4.1.24..688..6.4123.21.8.45646..21789

[champagne]

Hi blue
14..628..2.68...41..841.6.2.84..621.6.21.8..4.1.24..688..6.4123.21.8.45646..21789

amazing skfr rating 9.2 !!!!!

My draft of code sees 2 possible TH, but this is a wonderful example to work on.

I was expecting a "best case" with all bands and stacks morphs of the band index 0, here we have six different indexes

106 147 17 105 259 220

[ghfick]

The puzzle of jovi has an interesting advance. After the TH, one gets r1c1=6. Then, YZF_Sudoku reveals two different impossible patterns:

Impossible Pattern(789{r2c358,r3c239,r7c157,r8c28,r9c39,r1c7})
Impossible Pattern(789{r3c239,r5c127,r7c17,r8c28,r9c39,r1c7,r2c8})

both with a single guardian and each with several exclusions.

[champagne]

The puzzle of jovi has an interesting advance. After the TH, one gets r1c1=6. Then, YZF_Sudoku reveals two different impossible patterns:

Impossible Pattern(789{r2c358,r3c239,r7c157,r8c28,r9c39,r1c7})
Impossible Pattern(789{r3c239,r5c127,r7c17,r8c28,r9c39,r1c7,r2c8})

both with a single guardian and each with several exclusions.

Hi gordon,
Could you remind us the puzzle you are working on.??

[ghfick]

Can do:

Code: Select all

+-------+-------+-------+
| . 1 2 | . . . | . 3 4 |
| 3 5 . | . . . | 6 . 2 |
| 4 . . | . . . | 1 5 . |
+-------+-------+-------+
| . . . | . 1 7 | . . . |
| . . . | 5 . 2 | . . . |
| . . . | 8 6 . | . . . |
+-------+-------+-------+
| . 4 3 | . . . | . 2 5 |
| 1 . 5 | . . . | 3 . 6 |
| 2 6 . | . . . | 4 1 . |
+-------+-------+-------+
.12....3435....6.24.....15.....17......5.2......86.....43....251.5...3.626....41.


marek stefanik posted the puzzle with a post TH path based on remote triples. I think the Impossible Patterns are using the same principles as the RTs but perhaps the IPs are more like the TH.

[ghfick]

Here is the first part of the path [edited]:

Hidden Pair: 16 in r7c4,r7c6 => r7c4<>79,r7c6<>89
Hidden Pair: 25 in r4c7,r6c7 => r4c7<>89,r6c7<>79
Triplet Oddagon Type 1: 789r17c17,r2c38,r3c29,r8c28,r9c39 => r1c1<>789
Naked Single: r1c1=6
Naked Triple: in r2c3,r3c3,r9c3 => r4c3<>89,r5c3<>789,r6c3<>79,
Naked Triple: in r3c2,r3c3,r3c9 => r3c4<>79,r3c5<>789,r3c6<>89,
ImpossiblePattern(789{r2c358,r3c239,r7c157,r8c28,r9c39,r1c7})r2c46,r58c5<>4,r2c5<>7,r2c5<>8,r2c5<>9
ImpossiblePattern(789{r3c239,r5c127,r7c17,r8c28,r9c39,r1c7,r2c8})r5c5<>3,r5c12789,r1789c5,r4c4,r6c6<>9

[eleven]

I think the Impossible Patterns are using the same principles as the RTs but perhaps the IPs are more like the TH.

As shye showed recently, if you have (easily) proved RT's, this also proves TH. Same works for other IP's.
And for manual solvers they often can be a quicker way for getting eliminations than to search for usefull IP's (see Marek's solution).