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 }