Sudoku is a popular puzzle found in newspapers and magazines. The player is presented with a 9x9 grid divided into smaller 3x3 grids. Most of the spaces are blank but some are filled with numbers. The objective is to fill in all the blanks such that every row, column, and 3x3 square contains the numbers 1 through 9 without repeating any one number. You can play it online at WebSudoku.com.
The person credited for inventing Sudoku is Howard Garns, an American architect who originally called the game Number Place. It was renamed Su Doku in the mid-1980s when the game became popular in Japanese print media. From a mathematics perspective, completed Sudoku grids are known as Latin squares. You can generate Sudoku puzzles from a Latin square by removing numbers in a clever way so that the original Latin square can be recovered. From an AI perspective, Sudoku is a simple search problem. In fact, you can write a simple program to solve any Sudoku puzzle you are given!
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