#include <fstream>

using namespace std;

int i,j,n,m,t[17][17],s,v[17],smax=-100000;
ifstream fin("flip.in");
ofstream fout("flip.out");


void finalizare ()
{
    int sm = 0 , sl=0;
    for ( i=1 ; i<=n ; i++ )
    {
        sl = 0;
        for ( j=1 ; j<=m ; j++ )
        {
            sl = sl + t[i][j] * v[j] ;
        }
        if (sl < 0) sl = -sl;
        sm += sl;
    }

    smax = smax > sm ? smax : sm;
}

void bkt (int p)
{
    if ( p > m )
    {
        finalizare();
        return;
    }
    v[p]=1;
    bkt(p+1);
    v[p]=-1;
    bkt(p+1);
}


int main()
{
    fin>>n>>m;
    for ( i=1 ; i<=n ; i++ )
    {
        for ( j=1 ; j<=m ; j++ )
        {
            fin>>t[i][j];
        }
    }
    bkt(1);
    fout<<smax;

    return 0;
}