CC1.7.java

/*1.7  Write an algorithm such that if an element in an MxN matrix is 0, its entire row and column are set to 0.*/

public class Solution {
  public void setZero(int[][] matrix) {
    if(matrix==null || matrix.length==0) return;
    int n = matrix.length;
    int m = matrix[0].length;
    boolean[] row = new boolean[n];
    boolean[] col = new boolean[m]
    for(int i=0; i<n; i++)
      for(int j=0; j<m; j++) {
        if(matrix[i][j]==0) {
          row[i] = true;
          col[j] = true;
        }
      }
    for(int i=0; i<n; i++)
      for(int j=0; j<m; j++) {
        if(row[i] || col[j])
          matrix[i][j] = 0;
      }
  }
}