# include <fstream>
using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int a[16][16];
int sum(int n, int m)
{
    int poz, neg, suma=0, i, j;
    for (i=1; i<=n; i++)
    {
        poz=0;
        neg=0;
        for (j=1; j<=m; j++)
        {
            f>>a[i][j];
            poz+=a[i][j];
            neg-=a[i][j];
        }
        if (neg>poz)
            for (j=1; j<=m; j++)
            {
                a[i][j]*=-1;
                suma+=a[i][j];
            }
    }
}
int main()
{
    int n,m, suma1;
    f>>n>>m;
    suma1=sum(n, m);
    suma1=sum(m, n);
    g<<suma1;
}