When you first crack open a new sudoku puzzle, do you look at the rows or columns first? Or do you work in blocks? What’s your strategy?

  • sotolf@kbin.social
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    1 year ago

    What I usually do is going through the puzzle doing snydernotation first (marking when a number can only be in 2 places in a box)

    Most easy puzzles can be done with only that, then when it stops being fruitful I fully mark the puzzle up and start looking for things in roughly this order:

    • triples
    • x-wings
    • simple-fishes (skyscraper, 2-wing kites)
    • xy-wings
    • xyz-wings
    • swordfishes
    • chaining techniques

    That’s at least my basic rough order of going through solving a puzzle.

    • cujo@sh.itjust.works
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      1 year ago

      That’s… a lot. I’m assuming those are techniques for efficiently solving sudoku puzzles? I never thought about it, but it makes sense that there would be defined methodologies for tackling this kind of puzzle.

      • sotolf@kbin.social
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        1 year ago

        Yeah, there are a lot of techniques, mostly they are patterns that are quite easy to spot, so that you don’t have to manually go through the logic each time. Basically on the form of If a number can’t be here then it must be here, can’t be here, and must be there, because of this this one cell that looks like it’s detached from the rest can’t be this. Very difficult to only explain in text, but here is a link to some of the most common ones, if you are interested, with images and examples:

        X-wings especially: https://www.sudokuwiki.org/X_Wing_Strategy

        general explanation https://www.sudokuwiki.org/Getting_Started look on the left side of the page for different techniques sorted by difficulty.

        I also have a been the moderator of r/sudoku for years, where we usually help people out solving puzzles that they can’t solve :) It’s a lot of fun :)