#include    <fstream>
#define DIM 20
#define LL long long

using namespace std;

ifstream is("flip.in");
ofstream os("flip.out");

int n, m;
bool p[DIM];
LL a[DIM][DIM], v[DIM], s, maxs, stemp;

int main()
{
    int i, j;
    is >> n >> m;
    for(i = 1; i <= n; ++i)
        for(j = 1; j <= m; ++j) is >> a[i][j];

    while(!v[0]){
        j = m;
        while(v[j]){
            v[j] = 0;
            --j;
        }
        v[j] = 1;
        stemp = 0;
        for(i = 1; i <= n; ++i){
            s = 0;
            for(j = 1; j <= m; ++j){
                if(v[j])
                    s -= a[i][j];
                else s += a[i][j];
            }
            if(s < 0) s = (-1) * s;
            stemp += s;
        }
        if(stemp > maxs)
            maxs = stemp;
    }
    os << maxs << "\n";

    is.close();
    os.close();

    return 0;
}