Sudoku

I have a new vice, it's called Sudoku.

You may remember these, or something similar to them, from your school days, called Magic Squares. Sometimes they were a simple 3x3 grid requiring you to insert the numbers 1 thru 9 such that each row and column added up to a predesignated amount (basic algebra stuff).

Sudoku is more logic based (not that math is not logical) but Sudoku asks you to insert the numbers 1 thru 9 in each row, each column, and in each of the nine 3x3 grids.

When I first came across this in the LA Times it took me a good couple of hours to work the puzzle out. Each day the time to solve the puzzle became shorter. Then I realized some basic techniques to help solve the puzzle, and this morning I solved today's puzzle in under half an hour.

The easiest way to work the puzzle out is to, quite obviously, eliminate impossible numbers for each row and/or column so that, as Sherlock Holmes is reported to have said, once you have eliminated the impossible, whatever remains, however improbable, must be the truth.

An alternative means to solving these puzzles is to work out which number must go into a certain column, again by process of elimination. If you have two 3x3 grids with the same number in them, then you know by process of elimination which row or column in the third 3x3 grid (in a straight line) houses that particular number. If there is only one spare block in that row/column, it's obvious where that particular number must go. However, if there are two or three open blocks, then you must look to see if you can eliminate one or both of those superfluous blocks, thus eliminating the impossible, and arriving at the truth.

Solving Sudoku does not require any math-based skills, rather it requires logical thinking and deductive reasoning, and it's a good way to pass the time if you have nothing better to do.