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