Total solving techniques

Advanced methods and approaches for solving Sudoku puzzles

Total solving techniques

Postby Timmy » Sat Jun 25, 2005 8:43 am


My name is Tim and I attempted a Sudoku puzzle for the first time today (Australian, No.33).

I determined that the best way to approach the problem was:

1. go through each blank square, write in all the possible numbers it could be

2. Fill in all the squares that can be worked out by logical deduction

3. Choose a square where there are two possible alternatives and test one of the possible numbers. Hence solve the rest of the puzzle. (Obviously, if the puzzle doesnt work, then insert the other possible number and it should)

I took just under two hours to solve this 'medium' level puzzle. Out of interest, how long should they 'usually' take to solve? By the end of the puzzle I had streamlined my technique somewhat, but I initially wasted a lot of time trying to test different strategies due to my lack of experience.
What would be a 'good' time for solving a puzzle like this?
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Postby abailes » Sat Jun 25, 2005 8:54 am


Could you send us a link to your puzzle, or type it in, maybe?

It is difficult to know how hard The Australian is setting its puzzles, but you will probably find in time that you will get a medium level puzzle down to substantially less than half an hour. Its just a matter of practice.

Have a browse through some of the other threads on this forum. There are a number of techniques out there. Simes has a page which outlines them well if you find that link. If you are using a 'trial and error' technique from the beginning, that will not be the most effective use of your time, see other threads for pros and cons of using trial and error. Certainly most puzzles of a medium level should not need to use this and you should find the basic logical steps quicker.

Start with focussing on each 'number' at a time. Where are the existing 1s and what does this mean for the placement of 1s in the top-left 3x3 square, the top-middle 3x3 square and so on. Then look at the 2s, 3s etc. Be methodical about it. That technique alone should allow you to solve a medium puzzle much more easily.


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Postby simes » Sat Jun 25, 2005 12:47 pm

Simes has a page...

Indeed I do, it's at
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Location: UK

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