Problem
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?
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?
Code
void setZeroes(vector<vector<int> > &matrix) { // Start typing your C/C++ solution below // DO NOT write int main() function int m = matrix.size(); int n = matrix[0].size(); vector<bool> rows(m,false); vector<bool> cols(n,false); for(int i = 0; i < m; ++i){ for(int j = 0; j < n ; ++j){ if(matrix[i][j] == 0){ rows[i] = true; cols[j] = true; } } } for(int i = 0; i < m; ++i){ if(rows[i]){ for(int j = 0; j < n ; ++j){ matrix[i][j] = 0; } } } for(int j = 0; j < n; ++j){ if(cols[j]){ for(int i = 0; i < m ; ++i){ matrix[i][j] = 0; } } } }
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