Valid Sudoku
Last updated
Last updated
🧩 Problem Statement: Determine if a 9 x 9 Sudoku board is valid. Only the filled cells need to be validated according to the following rules:
Each row must contain the digits 1-9 without repetition.
Each column must contain the digits 1-9 without repetition.
Each of the nine 3 x 3 sub-boxes of the grid must contain the digits 1-9 without repetition.
📝 Note:
A Sudoku board (partially filled) could be valid but is not necessarily solvable.
Only the filled cells need to be validated according to the mentioned rules.
🔹 Example 1:
Input:
Output: true
🔹 Example 2:
Input:
Output: false
Explanation: The same as Example 1, except with the 5 in the top left corner being modified to 8. Since there are two 8's in the top left 3x3 sub-box, it is invalid.
📝 Constraints:
board.length == 9
board[i].length == 9
board[i][j]
is a digit 1-9
or '.'
.