Sudoku

ABOUT

Sudoku is played on a grid that is nine squares high and nine squares wide. The grid is then divided into smaller boxed areas that are three squares high and three squares wide. to complete the puzzle, you must fill in each row, column, and 3×3 box with the numbers 1 to 9. However:

Each number can appear only once in each row.
Each number can appear only once in each column.
Each number can appear only once in each 3×3 box.
There is only one solution for each puzzle.

Sudoku was invented by an American architect, Howard Garns, in 1979 and published by Dell Magazines under the name “Number Place”. It became popular in Japan in 1986, after it was published by Nikoli and given the name Sudoku, meaning single number.

TIPS and STRATEGY

Sure Thing Strategy

This strategy will give you an easy jump-start on your way to complete a sudoku board. its idea is to find a “sure number” to as many squares within the grid as possible. How do you do it? First, ask yourself, which number is missing? Choose a row, column, or 3×3 that has many numbers revealed. Choose an empty square in it.

Elimination Strategy

This strategy aims to quickly eliminate as many numbers as possible for each square. you can then whittle down the remaining possibilities to the correct number as you work through the puzzle. How do you do it? 1.) Chose any 3×3 box you like. Choose one square within it. 2.) Eliminate numbers that cannot be in this square. 3.) Write within the empty square the possibilities left. 4.) Fill all the 3×3’s in this way and then start to place sure numbers.

SUDOKU CHALLENGE
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