LeetCode 73: Set Matrix Zeroes

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

public class Solution {
    public void setZeroes(int[][] matrix) {
        int m = matrix.length;
        
        if (m == 0)
            return;
        
        int n = matrix[0].length;
        
        // Adopt hashtable to store coordinates of zeros
        Set<Integer> row = new HashSet<>();
        Set<Integer> column = new HashSet<>();
        
        // Store coordinates of zeros
        for (int i = 0; i < m; i++)
            for (int j = 0; j < n; j++)
                if (matrix[i][j] == 0)
                {
                    row.add(i);
                    column.add(j);
                }
                
        // Set zeros
        for (int i = 0; i < m; i++)
            for (int j = 0; j < n; j++)
                if (row.contains(i) || column.contains(j))
                    matrix[i][j] = 0;
    }
}