#include <iostream>
#include <fstream>
using namespace std;
ifstream in("flip.in");
ofstream out("flip.out");
const int maxn = 20;
int M[maxn][maxn];
int n, m;
int ans(int conf)
{
    int s = 0;
    for(int i = 0; i < n; i++)
    {
        if(conf & (1 << i))
            s += M[0][i + 1];
        else
            s -= M[0][i + 1];
    }
    return s;
}

int main()
{
    in >> n >> m;
    for(int i = 1; i <= n; i++)
    {
        for(int j = 1; j <= m; j++)
        {
            in >> M[i][j];
            M[0][j] += M[i][j];
        }
    }
    int mx = -(1 << 30);
    for(int conf = 0; conf < (1 << n); conf++)
        mx = max(mx, ans(conf));
    out << mx << "\n";
    return 0;
}