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People often forget that sudoku has a number of rules which make the game deterministic: Sudoku Rule: Don’t Guess Sudoku Rule: Unique Solution You aren't sup
by once_inc 4y ago
People often forget that sudoku has a number of rules which make the game deterministic:
Sudoku Rule: Don’t Guess
Sudoku Rule: Unique Solution
You aren't supposed to guess at any point, instead solving the puzzle by determining a number's position by logical deduction. You aren't supposed to just jot something down and hoping for the best.
Each sudoku puzzle should have one single valid solution. This has been used in the past by a devious creator that built his sudoku in such a way that the final n numbers to be filled led to two deduction paths; one leading to a single solution, the other to two possible solutions. As such, the only valid solution is the path where uniqueness remained.
I didn't look at the code for Sumplete, but using similar rules when building the puzzle seems obvious.
- cyborgx7 4y ago>This has been used in the past by a devious creator that built his sudoku in such a way that the final n numbers to be filled led to two deduction paths; one leading to a single solution, the other to two possible solutions. I don't see how this differs from there being three solutions, thereby not following the unique solution role. Like, what is functionally the difference between picking the path that leads to one solution rather than two, and just picking one of the two solutions at the end?
- PeterisP 4y agoA solution is not a "path" but the outcome i.e. a filled board. If there exist two options to write in the numbers which both fit the originally provided clues and the Sudoku criteria, then that puzzle has multiple solutions. It's worth noting that "don't guess" technically doesn't change anything at all - a full exhaustive search of all options starting from the top-left corner is a legitimate logical deduction tactic (and a legitimate proof in mathematics), even if suboptimal. If you eliminate all the possibilities of writing in numbers, you're supposed to be left only one way that fits the rules, the unique solution.