Arrays & Hashing
LC #36Medium
Valid Sudoku
Arrays & Hashing
Problem
Determine if a 9 x 9 Sudoku board is valid. Only the filled cells need to be validated according to the rules.
arrayhash-setmatrix
Constraints
- ›board.length == 9, board[i].length == 9
- ›board[i][j] is a digit 1-9 or '.'
Example
Input
board = [["5","3",".",".","7",".",".",".","."],...]Output
trueWhy
Check if each row, column, and 3x3 box contains digits 1-9 without repetition.