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Sudoku fans, share your solving strategies, talk about the types and levels of Sudoku you like best and get help.
1/2/2009 11:01:48 AM

finebergsdaughter
finebergsdaughter
Posts: 1
Hi. Are the hard and the challenging level sudoku puzzles in your publications "Satisfactory puzzles"? I'm new to the hard ones, and logic does not seem to be enough <g>. I'm considering making many copies of a puzzle with all the candidates marked, then guessing until the right combination appears. But I fear I will not learn anything that way.wink

1/3/2009 3:28:20 PM

fsk
fsk
Posts: 2
So far, all the Sudoku puzzles I've tried have had a unique solution.

Here's how I do hard/challenging puzzles. I use my elementary tactics as much as possible. Elementary tactics are: each number can appear at most once in each row, column, and box. For each square, I write down the candidates that can appear in each. If you can rule out all but two possibilities in two cells of a row, column, or box, then you can erase those two numbers as candidates in the rest of them.

I've written down all the candidates for each cell. Some cells have only two candidates. I then find a suitable cell, and pretend to continue solving both ways. If the cell is down to 35 as candidates, then I make the assumption 3 is there and another assumption that 5 is there. Usually, one of these leads to a contradiction, allowing me to put the other as the result.

There also are more advanced tactics you can Google for.

12/21/2014 3:27:45 PM

rachmeal12&12
rachmeal12&12
Posts: 1
After using "Elimination method", and checking very carefully, I find that I CANNOT complete the puzzle WITHOUT "cheating"; i.e., a current status report for each NEW number that I put in! This is AFTER making SURE, that ALL columns and ALL rows, have NO duplication!!! What is the secret, besides just "guessing" from THIS POINT ON?

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