Sudoku

Sudoku (数独, sūdoku^?, digit-single) (ⁱ/suːˈdoʊkuː/, /-ˈdɒ-/, /sə-/, originally called Number Place), is a logic-based,combinatorial number-placement puzzle. The objective is to fill a 9×9 grid with digits so that each column, each row, and each of the nine 3×3 subgrids that compose the grid (also called "boxes", "blocks", "regions", or "subsquares") contains all of the digits from 1 to 9. The puzzle setter provides a partially completed grid, which for a well-posed puzzle has a unique solution.

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