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July 25

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two digit sudoku and its answer

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please arrange a two digit sudoku with numbers and also its answer — Preceding unsigned comment added by 202.83.50.219 (talk) 10:56, 25 July 2013 (UTC)[reply]

There is a general procedure for producing an sudoku. In the first row, list the numbers 1 thru in order. For the next n rows, cyclically permute the first row by blocks of n. Then for row n+1 cyclically permute the first n slots of the first row, the second n slots of the first row, etc. For row n+2, do this to the second row, and so on. For instance, applying this procedure for a 9x9 sudoku gives
123456789
456789123
789123456
231564897
564897231
897231564
312645978
645978312
978312645
It's left as an exercise how to do this, eg, for whatever two digit size you had in mind (16x16, 25x25, 81x81). (Note: this clearly will not generate all possible suduko's, even if you are allowed to change the labels, but you just asked for one.) Sławomir Biały (talk) 12:24, 25 July 2013 (UTC)[reply]
To be fair, that's "only" a solution. The question how many squares are needed to make a sudoku unique hasn't been attacked above.
Wildly WP:ORing, I'd say it looks like that par tof the problem would be NP (complexity).
I guess a two-digit sudoku is one with 10 to 99 different symbols, and if you want numbers, those would be two digits per square. That would be, 3 < n < 10. (n=10 is ok if, contravening usual sudoku conventions, all combinations from 00 to 99 are used.) - ¡Ouch! (hurt me / more pain) 16:36, 27 July 2013 (UTC)[reply]