#include <fstream>

using namespace std;
ifstream fin("flip.in");
ofstream fout("flip.out");
int v[20], n, i, j, s, sp, a[20][20], m, maxim=-2000000000;

int main()
{
    fin>>n>>m;
    for ( i=1; i <= n; i++ )
        for ( j=1; j <= m; j++)
            fin >> a[i][j];
    while ( v[0] == 0 )
    {
        i=n;
        while ( v[i] == 1 )
            v[i]=0, i--;
        v[i]=1;
        s=0;
        for ( j=1; j <= m; j++ )
        {
            sp=0;
            for ( i=1; i <= n; i++ )
            {
                if ( v[i] == 0 )
                    sp += a[i][j];
                else
                    sp -= a[i][j];
            }

            s += max ( sp, -sp );
        }
        if ( s > maxim )
            maxim = s;
    }
    fout << maxim;
    return 0;
}