Soduku
Techniques

soduku
faq
techniques
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There is no mathematics involved in solving Soduku puzzles as they can be completed using logic. There are however a number of techniques or stategies that can be used.

One useful solving technique is cross-hatching. This involves reading rows to identify which three-cell line must have a certain number, and reading down the columns to discover which of these cells must contain the number.

A basic yet vital stategy that you should be used is counting. You must look through the numbers in rows, columns or 3x3 boxes to see what can go where based on the fact that each row, column and 3x3 box contains the numbers 1 to 9 just once.

Another technique that can be used is marking up. For this you can write down (perhaps in the top corner of the square) the different numbers that can possibly be placed in each square. A problem with this is that original puzzles printed in a newspaper usually are too small to accommodate more than a few digits of normal handwriting.