[LeetCode] Set Matrix Zeros

 1 public class Solution {
 2     public void setZeroes(int[][] matrix) {
 3         int m=matrix.length;
 4         int n=matrix[0].length;
 5         boolean hasZeroCol = false, hasZeroRow = false;
 6
 7         for (int i=0; i<m; i++)
 8             if (matrix[i][0] == 0) { hasZeroCol = true; break; }
 9
10         for (int j=0; j<n; j++)
11             if (matrix[0][j] == 0) { hasZeroRow = true; break; }
12
13         for (int i=1; i<m; i++) {
14             for (int j=1; j<n; j++) {
15                 if (matrix[i][j] == 0) {
16                     matrix[0][j] = 0;
17                     matrix[i][0] = 0;
18                 }
19             }
20         }
21
22         for (int i=1; i<m; i++) {
23             for (int j=1; j<n; j++) {
24                 if (matrix[i][0] == 0 || matrix[0][j] == 0)
25                     matrix[i][j] = 0;
26             }
27         }
28
29         if (hasZeroCol)
30             for (int i=0; i<m; i++) matrix[i][0] = 0;
31
32         if (hasZeroRow)
33             for (int i=0; i<n; i++) matrix[0][i] = 0;
34
35
36     }
37 }