class Solution {public:    void setZeroes(vector<vector<int> > &matrix) {        int rows = matrix.size();        int cols = matrix[0].size();                bool col_has_zero = false;        bool row_has_zero = false;                for (int i=0; i<cols; i++) {            if (matrix[0][i] == 0) {                 row_has_zero = true;                break;            }        }                for (int i=0; i<rows; i++) {            if (matrix[i][0] == 0) {                col_has_zero = true;                break;            }        }                for (int i=1; i<rows; i++) {            for (int j=1; j<cols; j++) {                if (matrix[i][j] != 0) continue;                matrix[i][0] = 0;                matrix[0][j] = 0;            }        }                for (int i=1; i<rows; i++) {            for (int j=1; j<cols; j++) {                if (!matrix[i][0] || !matrix[0][j]) {                    matrix[i][j] = 0;                }            }        }        for (int i=0; row_has_zero && i<cols; i++) matrix[0][i] = 0;        for (int i=0; col_has_zero && i<rows; i++) matrix[i][0] = 0;    }};