Sudoku
Fill in the blanks on a 9x9 grid so that each column, row, and 3x3 square contains the digits 1 to 9 only once.
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Sudoku is a logic-based number puzzle whose objective is to fill a 9x9 grid so that each column, row, and 3x3 square contains the digits 1 to 9 only once. A partially completed grid is provided, and it is your job to fill in the blanks. Choose one of six levels of difficulty: easy, medium, hard, very hard, insane, and inhuman.
