- Code: Select all
XY-chain(7)
*-----------*
|1..|6.3|..4|
|.7.|2.8|.9.|
|...|.4.|...|
|---+---+---|
|93.|...|.68|
|..7|.8.|3..|
|24.|...|.57|
|---+---+---|
|...|.6.|...|
|.5.|4.2|.1.|
|8..|9.5|..3|
*-----------*
*--------------------------------------------------------------------*
| 1 29 259 | 6 579 3 | 257 8 4 |
|*34 7 *34 | 2 15 8 | 56 9 156 |
| 56 8 2569 | 17 4 179 | 257 3 125 |
|----------------------+----------------------+----------------------|
| 9 3 15 | 157 2 147 | 14 6 8 |
| 56 16 7 | 15 8 49 | 3 24 29 |
| 2 4 8 | 3 19 6 | 19 5 7 |
|----------------------+----------------------+----------------------|
|*34 129 -12349 | 8 6 17 | 2459 247 259 |
| 7 5 69 | 4 3 2 | 8 1 69 |
| 8 126 1246 | 9 17 5 | 246 247 3 |
*--------------------------------------------------------------------*
Uniqueness rectangle + swordfish and multiple colors solves the puzzle.
The other two are not nearly as obvious, but I think these are much easier solutions than the suggested XY-chains length 9 & 10:
- Code: Select all
XY-chain (9)
*-----------*
|.8.|2.7|.5.|
|4..|9.6|..2|
|...|.5.|...|
|---+---+---|
|15.|...|.27|
|..7|...|9..|
|32.|...|.86|
|---+---+---|
|...|.4.|...|
|2..|6.9|..8|
|.9.|5.3|.1.|
*-----------*
*-----------------------------------------------------------*
| 69 8 136 | 2 13 7 | 4 5 139 |
| 4 137 5 | 9 138 6 | 78 37 2 |
| 79 137 2 | 1348 5 148 | 678 69 139 |
|-------------------+-------------------+-------------------|
| 1 5 9 | 48 6 48 | 3 2 7 |
| 8 6 7 | 13 123 12 | 9 4 5 |
| 3 2 4 | 7 9 5 | 1 8 6 |
|-------------------+-------------------+-------------------|
| 5 137 1368 | 18 4 128 | 267 69 39 |
| 2 4 13 | 6 17 9 | 5 37 8 |
| 67 9 68 | 5 278 3 | 267 1 4 |
*-----------------------------------------------------------*
If r3c8=9 => r3c1=7 => r3c29=(13) => r3c46=(48) => BUG-lite in r23c2, r12c5, r13c9 => r3c8<>9
- Code: Select all
XY-chain (10)
*-----------*
|..5|...|3..|
|.8.|.9.|.7.|
|6..|.2.|..1|
|---+---+---|
|...|6.4|...|
|.31|...|79.|
|...|9.1|...|
|---+---+---|
|5..|.8.|..2|
|.9.|.6.|.5.|
|..3|...|6..|
*-----------*
*--------------------------------------------------*
| 12 12 5 | 78 4 78 | 3 6 9 |
| 3 8 4 | 1 9 6 | 2 7 5 |
| 6 7 9 | 3 2 5 | 48 48 1 |
|----------------+----------------+----------------|
| 9 5 27 | 6 37 4 | 18 123 38 |
| 4 3 1 | 28 5 28 | 7 9 6 |
| 78 6 278 | 9 37 1 | 5 23 4 |
|----------------+----------------+----------------|
| 5 14 6 | 47 8 37 | 9 13 2 |
| 178 9 78 | 24 6 23 | 148 5 378 |
| 278 24 3 | 5 1 9 | 6 48 78 |
*--------------------------------------------------*
If r4c9=3 => r4c5=7 => r4c3=2 => BUG-lite in r6c13, r8c39, r9c19 => r4c9<>3
As many people already have pointed out the simpler solutions to tareks ALS-XY example, I did not put that on the list either. All other puzzles were added.
I think there is probably enough of XY-chain examples by now, but plenty of room for puzzles that require other techniques.
Ruud wrote:There must be a few examples in my Benchmark Sudoku List that you can use.
Actually, I posted the list on this forum, so it can be used as source for solving technique samples. We could join forces and complete the list with advanced solving techniques that are still missing.
Yes, that's a nice list you've got. I started this thread for manual solvers who wish to try advanced techniques, that's why I think it's good to have several examples of all techniques. As your is intended for computer-solver testing you only need one of each, but there sure is a lot of good examples in your list that could be used here as well. I'll post my reverse-BUG example to your list as it seems to be missing.
RW