Dr. Sudoku

Sudoku originally called Number Place is a logic-based number-placement puzzle.

Dr. SudokuSudoku 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 sub-grids that compose the grid 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.Completed puzzles are always a…