leetcode_set_matrix_zeroes

class Solution {
public:
    void setZeroes(vector<vector<int>>& matrix) {
        int m = matrix.size();
        int n = matrix[0].size();
        set<int> rows;
        set<int> cols;
        for(int i = 0; i < m; i++)
        {
            for(int j = 0; j < n; j++)
            {
                if(matrix[i][j] == 0)
                {
                    rows.insert(i);
                    cols.insert(j);
                }
            }
        }
        auto rows_it = rows.begin();
        for(; rows_it != rows.end(); rows_it++)
        {
            for( int j = 0; j < n; j++)
                matrix[*rows_it][j] = 0;
        }
        auto cols_it = cols.begin();
        for(; cols_it != cols.end(); cols_it++)
        {
            for(int i = 0; i < m; i++)
                matrix[i][*cols_it] = 0;
        }
    }
};