Diagonal Samurai Sudoku X for New Year’s Day – this is the only place you can find these kind of Sudoku puzzles!
Warning: Today’s puzzle is the MOST difficult Samurai X yet!
Basically, not only do you have to fight against 5 interconnected Sudokus, but you also need to be carefull about the diagonals: ALL diagonals in the puzzle must contain one occurrence of each 19 digit. The diagonals are marked in the puzzle so you wouldn’t forget about them.
(click to download or rightclick to save the image)
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To see the solution to this puzzle click here
UPDATE: Download this file to see the solution up to the critical point, when you must use “XWing” (for number 5 in the upper left subpuzzle), which indirectly solves one cell and after that it should be relatively easy to do (no fancy stuff required).
I warned you – this was an extremely difficult puzzle :).
5 Comments
To solve this one do we need any special technique or is it business as usual?
Best regards.
Fernando Castro
Fernando, this one is extremely difficult because it requires XWing to solve.
Hint: XWing is for number 5 in the upperleft 9×9 subSudoku.
Another Samurai solver program has told me this is not solvable! I certainly couldn’t solve it.
Sue, as far as i know there are no other Samurai programs that can handle Samurai “X”, which means that the diagonals must also contain all numbers 19.
If you don’t take that into consideration, then there are probably multiple solutions.
I will upload an image showing the position up to the critical move required to solve this puzzle.
I have finally solved the Samurai X – HNY however I came back to the site as the only way I found to solve it was to run two alternatives until it became clear which worked. Oddly (before having looked at your tip) I chose the 59 combination from the right column of the top left puzzle as the two alternatives. 5 in the lower of the two quickly produced an error which left 9 as the key to the rest of the solution. The whole puzzle then took no more than an hour or so to solve. I was curious as to why I couldn’t see a logical solution and saw your tip to use xwing. Having looked at the xwing method I am still none the wiser, what am I missing? Many thanks though for a thoroughly frustrating puzzle.