#include <fstream>
#include <bitset>
#include <cmath>

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

int main () {
    int n, m, matrice[20][20]; fin >> n >> m;
    for (int i = 1; i <= n; i += 1)
        for (int j = 1; j <= m; j += 1)
            fin >> matrice[i][j];

    int nr = (1 << m), res = 0;

    for (int submult = 1; submult < nr; submult += 1) {
        std::bitset<20> flip(submult);

        int suma = 0;
        for (int i = 1; i <= n; i += 1) {
            int sumaColoana = 0;
            for (int j = 1; j <= m; j += 1)
                if (flip[j - 1] == 1)
                    sumaColoana -= matrice[i][j];
                else
                    sumaColoana += matrice[i][j];

            sumaColoana = std::abs (sumaColoana);

            suma += sumaColoana;
        }

        res = std::max (res, suma);
    }

    fout << res;
    return 0;
}