#include<fstream>
using namespace std;
int n,m;
long a[22][22], b[22],rez,suma,s;

int calcul()
{
    int i,j;
    suma=0,s=0;
    for(i=1;i<=n;i++)
    {
        suma=0;
        for(j=1;j<=m;j++)
        suma+=a[i][j]*b[j];
        if(suma<0) suma=-suma;
        s+=suma;
    }
    return s;
}
void back(int k)
{
    if(k==m+1)
    {
        suma=calcul();
        if (suma>rez) rez=suma;
    }
    else
    {
        b[k]=-3;
        while(b[k]<1)
        {
            b[k]+=2;
            back(k+1);
        }
    }
}
int main ()
{
    ifstream f("flip.in");
    ofstream g("flip.out");
    int i,j;
    f>>n>>m;
    for(i=1;i<=n;i++) for(j=1;j<=m;j++) f>>a[i][j];
    back(1);
    g<<rez;
}