Sandwich Sudoku 28/05/21

Post the puzzle or solving technique that's causing you trouble and someone will help

Sandwich Sudoku 28/05/21

Postby Fortesque92 » Fri May 28, 2021 2:10 am

Stuck right at the end! any ideas?

https://ibb.co/zPKzLPk
Fortesque92
 
Posts: 94
Joined: 30 June 2020

Re: Sandwich Sudoku 28/05/21

Postby Leren » Fri May 28, 2021 5:32 am

Code: Select all
*-------------------------------*
| 1 28 4  | 5  6 23 | 38   7  9 |
| 5 28 7  | 23 9 4  | 1    38 6 |
| 9 3  6  | 7  1 8  | 4    5  2 |
|---------+---------+-----------|
| 2 7  8  | 1  4 9  | 5    6  3 |
| 3 6  9  | 8  2 5  | 7    4  1 |
| 4 1  5  | 6  3 7  | 9    2  8 |
|---------+---------+-----------|
| 6 5  23 | 9  7 1  |*3-28 38 4 |
| 7 9  23 | 4  8 23 | 6    1  5 |
| 8 4  1  | 23 5 6  | 23   9  7 |
*-------------------------------*

Bug+1 => r7c7 = 3. You can read about the BUG principle, for example, here or here.

Leren
Leren
 
Posts: 5118
Joined: 03 June 2012

Re: Sandwich Sudoku 28/05/21

Postby Fortesque92 » Sat May 29, 2021 3:15 am

Wow, thank you! I half understand the principal lol

Do you think it was a flaw in my solving, in the design of the puzzle or was this supposed to happen?
Fortesque92
 
Posts: 94
Joined: 30 June 2020

Re: Sandwich Sudoku 28/05/21

Postby Leren » Sat May 29, 2021 3:55 am

If the dark black numbers in the diagram are the only clues, there are only 13 of them, and reading the stuff at the bottom tells me that this must be some sort of variant with some extra constraints.

A normal sudoku must have at least 17 clues for a unique solution, so you apparently got to your solved state using the extra constraints.

In this case the final solution was a valid sudoku grid, so for this puzzle, the extra information seems to be consistent with the extra Sudoku clue requirements.

Leren
Leren
 
Posts: 5118
Joined: 03 June 2012


Return to Help with puzzles and solving techniques