Sudoku (/suːˈdoʊkuː, -ˈdɒk-, sə-/; Japanese: 数独, romanized: sūdoku,
lit. 'digit-single'; originally called Number Place)[1] is a
logic-based,[2][3] combinatorial[4] number-placement puzzle. In classic
Sudoku, 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", or "regions") 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 single solution.
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