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.

click to show follow up.

Follow up:

Did you use extra space?
A straight forward solution using O(mn) space is probably a bad idea.
A simple improvement uses O(m + n) space, but still not the best solution.
Could you devise a constant space solution?

分析：将数组中为0元素所在的行和列都置0。首先找到这些元素，分别开两个数组记录所在行和列，将这些行和列分别置0

运行时间：87ms

 

class Solution {
public:
    void setZeroes(vector<vector<int>>& matrix) {
        int row = matrix.size();
        int col = matrix[0].size();
        
        vector<int> vRow(row, 0);
        vector<int> vCol(col, 0);
        for(int i = 0; i < row; i++){
            for(int j = 0; j < col; j++){
                if(matrix[i][j] == 0){
                    vRow[i] = 1;
                    vCol[j] = 1;
                }
            }
        }
        for(int i = 0; i < row; i++){
            if(vRow[i] == 1){
                for(int j = 0; j < col; j++) matrix[i][j] = 0;
            }
        }
        for(int j = 0; j < col; j++){
            if(vCol[j] == 1){
                for(int i = 0; i < row; i++) matrix[i][j] = 0;
            }
        }
        return;
    }
};