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