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.

Example 1:

Input: 
[
  [1,1,1],
  [1,0,1],
  [1,1,1]
]
Output: 
[
  [1,0,1],
  [0,0,0],
  [1,0,1]
]

Example 2:

Input: 
[
  [0,1,2,0],
  [3,4,5,2],
  [1,3,1,5]
]
Output: 
[
  [0,0,0,0],
  [0,4,5,0],
  [0,3,1,0]
]

Follow up:

• 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?

题目链接：https://leetcode.com/problems/set-matrix-zeroes/

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

 同样的代码，leetcode的runtime就是bullshit，参考参考吧