Given a m x n matrix, if an element is 0, set its entire row and column to 0. Do it in place.

class Solution {

public:

void setZeroes(vector<vector<int>>& matrix) {

int m = matrix.size();

int n = matrix[0].size();

int i,j;

//set the flag for the first row/column

bool firstRow = false;

bool firstCol = false;

for(int i =0;i<n;i++)

if(matrix[0][i] == 0)

{

firstRow = true;

break;

}

for(int j=0;j<m;j++)

if(matrix[j][0] == 0)

{

firstCol = true;

break;

}

for( j = 1;j<m;j++)

for( i = 1;i<n;i++)

{

if(matrix[j][i] == 0)

{

matrix[0][i] = 0; //first row

matrix[j][0] = 0; //frist column

}

}

for( j = 1;j<m;j++)

for( i = 1;i<n;i++)

{

if(matrix[0][i] == 0 || matrix[j][0] == 0)

matrix[j][i] = 0;

}

if(firstRow)

{

for( i = 0;i<n;i++) matrix[0][i] = 0;

}

if(firstCol)

{

for( j = 0;j<m;j++) matrix[j][0] = 0;

}

}

};