#include <fstream>

using namespace std;

ifstream cin ("flip.in");
ofstream cout ("flip.out");

int mat[17][17], n, m, maxx, sum, sum_col;
int viz[17];

void read()
{
    cin >> n >> m;
    for(int i = 1; i <= n; ++i)
    {
        for(int j = 1; j <= m; ++j)
        {
            cin >> mat[i][j];
        }
    }
}

void solve()
{
    sum = 0;
    for(int i = 1; i <= m; ++i)
    {
        sum_col = 0;
        for(int j = 1; j <= n; ++j)
        {
            sum_col += viz[j] * mat[j][i];
        }
        if(sum_col < 0)
        {
            sum += (-1) * sum_col;
        }
        else
        {
            sum += sum_col;
        }
    }
    if(sum > maxx)
    {
        maxx = sum;
    }
}

void bkt(int step)
{
    if(step > n)
    {
        solve();
        return ;
    }
    viz[step] = 1;
    bkt(step + 1);
    viz[step] = -1;
    bkt(step + 1);
    viz[step] = 1;
}

void print()
{
    /*for(int i = 1; i <= n; ++i)
    {
        cout << line[i] << " ";
    }
    cout << "\n";*/
    cout << maxx << "\n";
}

int main()
{
    read();
    bkt(1);
    print();
    return 0;
}