73. Set Matrix Zeroes
Given an m x n integer matrix matrix, if an element is 0, set its entire row and column to 0’s, and return the matrix.
You must do it in place.
- Time : O(nm)
- Space : O(1)
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| class Solution {
public:
void setZeroes(vector<vector<int>>& matrix) {
int n = matrix.size(), m = matrix[0].size();
bool zeroCol0 = false;
for(int i = 0; i < n; i++) {
zeroCol0 |= !matrix[i][0];
for(int j = 1; j < m; j++)
if(!matrix[i][j])
matrix[i][0] = matrix[0][j] = 0;
}
for(int i = n - 1; i >= 0; i--) {
for(int j = m - 1; j >= 1; j--) {
if(!matrix[i][0] || !matrix[0][j]) matrix[i][j] = 0;
}
}
if(zeroCol0) {
for(int i = 0; i < n; i++)
matrix[i][0] = 0;
}
}
};
|
