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LeetCode 73. Set Matrix Zeroes (javascript)

Given an m x n matrix. If an element is 0, set its entire row and column to 0. Do it in-place.

Follow up:

  • A straight forward solution using O(mn) space is probably a bad idea.
  • A simple improvement uses O(m + n) space, but still not the best solution.
  • Could you devise a constant space solution?

Example 1:

Input: matrix = [[1,1,1],[1,0,1],[1,1,1]]
Output: [[1,0,1],[0,0,0],[1,0,1]]

Example 2:

Input: matrix = [[0,1,2,0],[3,4,5,2],[1,3,1,5]]
Output: [[0,0,0,0],[0,4,5,0],[0,3,1,0]]

Constraints:

  • m == matrix.length
  • n == matrix[0].length
  • 1 <= m, n <= 200
  • -231 <= matrix[i][j] <= 231 - 1

Solution:

/**
 * @param {number[][]} matrix
 * @return {void} Do not return anything, modify matrix in-place instead.
 */
var setZeroes = function(matrix) {
    let rowHasZero = [];
    let colHasZero = [];
    
    for (let i = 0; i < matrix.length; i++) {
        for (let j = 0; j < matrix[i].length; j++) {
            if (matrix[i][j] === 0) {
                rowHasZero.push(i);
                colHasZero.push(j);
            }
        }
    }
    
    for (let i = 0; i < matrix.length; i++) {
        for (let j = 0; j < matrix[i].length; j++) {
            if (rowHasZero.includes(i) || colHasZero.includes(j)) {
                matrix[i][j] = 0;
            }
        }
    }
};