Category Archive: Sudoku

Mar 04 2013

Sudoku: advanced techniques


Sudoku puzzles are classified according to their difficulty. My old newspaper, the LA Times, did so as Gentle, Moderate, Tough, and Diabolical. Sites like Daily Sudoku have basically the same division, though the names are different (hard and very hard instead of tough and diabolical). Difficulty is determined by the techniques needed to solve the …

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Mar 03 2013

Sudoku: medium difficulty methods


A simple elimination algorithm that searches box-by-box, row or column will solve most Gentle and maybe even some Moderate puzzles. The final simple technique knocks out pretty much any remaining Gentle: Technique 4: Enumeration If the previous searches fail, try checking each square on an individual basis to see what numbers it can "see". For …

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Feb 23 2013

Sudoku: more basics


It's possible to solve a Gentle Sudoku with only a box-by-box search technique. While this is the first technique I will normally apply, it is not the only one necessary to solve most Gentle puzzles. Sudoku has 3 rules: every 3x3 highlighted box must have 1-9, every row must have 1-9, and every column must …

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Feb 18 2013

Sudoku: the basics


Those of us who think we'll live a long time (not me) have a couple near certain conditions to look forward to. For men, it's prostate cancer. But for either gender, it's dementia. Puzzles ward off dementia. I'm not all that good at puzzles. Over the years I've done crosswords, but they require a bit …

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