#include <fstream>

using namespace std;

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

const int NMax = 16, oo = 2e9;

int N, M, A[NMax + 5][NMax + 5], V[NMax + 5][NMax + 5], C[NMax + 5], Lim, Sol = -oo;

int Solve()
{
    int Ans = 0;

    for(int j = 1; j <= M; j++)
    {
        C[j] = 0;

        for(int i = 1; i <= N; i++)
            C[j] += V[i][j];

        Ans += abs(C[j]);
    }
    return Ans;
}

int main()
{
    fin >> N >> M; Lim = (1 << N);

    for(int i = 1; i <= N; i++)
        for(int j = 1; j <= M; j++)
            fin >> A[i][j];

    for(int i = 0, s; i < Lim; i++)
    {
        for(int k = 1, x = i; k <= N; k++, x >>= 1)
        {
            s = ((x & 1) ? -1 : 1);

            for(int j = 1; j <= M; j++)
                V[k][j] = s * A[k][j];
        }
        Sol = max(Sol, Solve());
    }
    fout << Sol << '\n';

    fin.close();
    fout.close();

    return 0;
}