#include<fstream.h>
int main()
{
 ifstream fin("flip.in");
 ofstream fout("flip.out");
 unsigned int n,m,i,j,b[2];
 long a[100][16],s=0;
 fin>>n>>m;
 for(i=0;i<n;i++)
    for(j=0;j<m;j++)
       {fin>>a[i][j];
	if(!(a[i][j])){b[0]=i;b[1]=j;}}

 for(i=0;i<n;i++)
    for(j=0;j<m;j++)
	if(i==b[0]||j==b[1]) s+=(-1*a[i][j]);
	else s+=a[i][j];
 fout<<s;
 fin.close();
 fout.close();
 return 0;
}