carcul wrote:Little time required: r5c7 cannot be "1", otherwise the puzzle would have more than one solution.
That is true, but not very easy to spot. This doesn't pretend to be a better solution, but I found an interesting move here. First some BUG-lites:
- Code: Select all
*-----------------------------------------------------------*
| 5 6 8 | 4 2 7 | 3 19 19 |
| 39 39 2 | 5 1 8 | 6 4 7 |
| 47 47 1 | 9 6 3 | 2 5 8 |
|-------------------+-------------------+-------------------|
| 1348 34 9 | 6 5 2 | 7 38 14 |
| 138 25 6 | 18 7 4 | 15 2389 29 |
| 148 25 7 | 18 3 9 | 145 28 6 |
|-------------------+-------------------+-------------------|
| 79 79 5 | 3 8 6 | 14 12 124 |
| 2 8 3 | 7 4 1 | 9 6 5 |
| 6 1 4 | 2 9 5 | 8 7 3 |
*-----------------------------------------------------------*
BUG-lite in r2347c12 => r4c1<>34
BUG-lite in r157c89 => r7c9<>1
BUG-lite in r56c2478 => r5c8<>2
Brings us here:
- Code: Select all
*--------------------------------------------------*
| 5 6 8 | 4 2 7 | 3 19 19 |
| 39 39 2 | 5 1 8 | 6 4 7 |
| 47 47 1 | 9 6 3 | 2 5 8 |
|----------------+----------------+----------------|
|*18 #34 9 | 6 5 2 | 7 *38 14 |
|#138 25 6 | 18 7 4 | 15 389 29 |
| 148 25 7 | 18 3 9 | 145 28 6 |
|----------------+----------------+----------------|
| 79 79 5 | 3 8 6 | 14 12 24 |
| 2 8 3 | 7 4 1 | 9 6 5 |
| 6 1 4 | 2 9 5 | 8 7 3 |
*--------------------------------------------------*
Is this some sort of ALS? We know that either r4c1=1 or r4c8=3, but there's a strong link in box 4, [r5c1]=3=[r4c2], which tells us that r5c1<>1. Or perhaps it's just a normal short forcing chain... The rest is easily solved with the BUG+3 (r6c8<>8).
JPF wrote:We have to wait until the :
Too bad for you, Santa visits the homes in Finland already on the 24th!
RW