c_cpp 设置Matrix Zeroeshttp：//oj.leetcode.com/problems/set-matrix-zeroes/

Posted 2021-05-14

class Solution {
public:
    void setZeroes(vector<vector<int> > &matrix) {
        /*
        //This solution use o(m+n) spaces
        int m = matrix.size();
        if(m == 0){
            return;
        }
        int n = matrix[0].size();
        vector<bool> column(m, false);
        vector<bool> row(n, false);
        for(int i = 0; i < m; i++){
            for(int j = 0; j < n; j++){
                if(matrix[i][j] == 0 ){
                    column[i] = true;
                    row[j] = true;
                }
            }
        }
        for(int i = 0; i < m; i++){
            for(int j = 0; j < n; j++){
                if(column[i] || row[j] ){
                    matrix[i][j] = 0;
                }
            }
        }*/
        int m = matrix.size();
        if(m == 0){
            return;
        }
        int n = matrix[0].size();

        bool is_col_0 = false;
        bool is_row_0 = false;
        for(int i = 0; i < m; i++){
            if(matrix[i][0] == 0){
                is_col_0 = true;
            }
        }
        for(int j = 0; j < n; j++){
            if(matrix[0][j] == 0){
                is_row_0 = true;
            }
        }
        
        for(int i = 1; i < m; i++){
            for(int j = 1; j < n; j++){
                if( matrix[i][j] == 0 ){
                    matrix[i][0] = 0;
                    matrix[0][j] = 0;
                    
                }
            }
        }

        for(int i = 1; i < m; i++){
            for(int j = 1; j < n; j++){
                if(matrix[0][j] == 0 || matrix[i][0] == 0){
                    matrix[i][j] = 0;
                }
            }
        }
        if(is_col_0){
            for(int i = 0; i < m; i++){
                matrix[i][0] = 0;
            }
        }
        if(is_row_0){
            for(int j = 0; j < n; j++){
                matrix[0][j] = 0;
            }
        }
    }
};