#include<fstream.h>

void check(unsigned int i,long a[100][16],unsigned int n,unsigned int sw,unsigned int &k)
{
 if(!sw)
 {for(int j=0;j<n;j++)
    if(!(a[i][j])) k++;}
 else
 {
  for(int j=0;j<n;j++)
    if(!a[j][i]) k++;
 }
 }

int main()
{
 ifstream fin("flip.in");
 ofstream fout("flip.out");
 unsigned int n,m,i,j,kn=0,km=0;
 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];

 for(i=0;i<n;i++)
    {
    check(i,a,n,0,kn);
    for(j=0;j<m;j++)
       {
	check(j,a,m,1,km);
	if((kn+km)%2) s+=-a[i][j];
        else s+=a[i][j];

        km=0;
       }
     kn=0;
    }
 fout<<s;
 fin.close();
 fout.close();
 return 0;
}