Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place.
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?
class Solution {
public:
void setZeroes(vector<vector<int> > &matrix) {
// Start typing your C/C++ solution below
// DO NOT write int main() function
vector<int> zeroRow(matrix.size());
vector<int> zeroCol(matrix[0].size());
for(int i=0;i<matrix.size();i++)zeroRow[i]=0;
for(int j=0;j<matrix[0].size();j++)zeroCol[j]=0;
for(int i=0;i<matrix.size();i++){
for(int j=0;j<matrix[i].size();j++)
{
if(matrix[i][j]==0){
zeroRow[i]=1;
zeroCol[j]=1;
}
}
}
for(int i=0;i<matrix.size();i++){
for(int j=0;j<matrix[i].size();j++)
{
if(zeroRow[i]==1||
zeroCol[j]==1)
matrix[i][j]=0;
}
}
}
};
//常数空间占用请使用第一列及第一行