In Sudoku there are onlly a few basic rules. You have to fill in the 9x9 grid so that every row, every collum and every 3x3 box contains the numbers 1 through 9, which means that there cannot be an overlap of numbers in any row, collum or 3x3 box.

Soku is a speed version of sudoku. In Soku there is another rule that states that every row or collum in any 3x3 box contains the same set of numbers.

--10 9 8 7 6 5 4 3 2 1   

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