#include <iostream>
#include <fstream>
using namespace std;

ifstream intrare("flip.in");
ofstream iesire("flip.out");

const int nmax=16, mmax=16;
int v[nmax+1][mmax+1], u[nmax+1];
int n, m, sol;

void bt(int x)
{
    if (x==n+1)
    {
        int aux=0;
        for (int j=1; j<=m; j++)
        {
            int s=0;
            for (int i=1; i<=n; i++)
                s+=v[i][j]*u[i];
            if (s<0)
                aux-=s;
            else
                aux+=s;
        }
        if (aux>sol)
            sol=aux;
    }
    else
    {
        u[x]=1;
        bt(x+1);
        u[x]=-1;
        bt(x+1);
    }
}

int main()
{
    intrare>>n>>m;
    for (int i=1; i<=n; i++)
        for (int j=1; j<=m; j++)
            intrare>>v[i][j];
    bt(1);
    iesire<<sol<<endl;

    return 0;
}