#include <fstream>

using namespace std;
ifstream fin("flip.in");
ofstream fout("flip.out");

int n, m;
long long answer = -1e9;
int table[20][20];
bool verif[20];

void Verif();
void Choose(int k);

int main()
{
    fin >> n >> m;
    for(int i = 1; i <= n; ++i)
        for(int j = 1; j <= m; ++j)
            fin >> table[i][j];
    Choose(1);
    fout << answer;
}

void Verif()
{
    long long sum = 0;
    for (int j = 1; j <= m; ++j)
    {
        long long A = 0, B = 0;
        for (int i = 1; i <= n; ++i)
        {
            if (verif[i])
            {
                A -= table[i][j];
                B += table[i][j];
            }
            else
            {
                A += table[i][j];
                B -= table[i][j];
            }
        }
        sum += max(A, B);
    }
    answer = max(answer, sum);
}
void Choose(int k)
{
    if (k == n + 1)
    {
        Verif();
        return;
    }
    verif[k] = true;
    Choose(k + 1);
    verif[k] = false;
    Choose(k + 1);
}