#include <bits/stdc++.h>
using namespace std;

int flip[16][16];
int N, M, S;

void test(long long mask)
{
    int ss[M];
    for (int j = 0; j < M; j++)
        ss[j] = 0;
    for (int i = 0; i < N; i++)
    {
        if (mask & (1 << i))
        {
            for (int j = 0; j < M; j++)
                ss[j] -= flip[i][j];
        }
        else
        {
            for (int j = 0; j < M; j++)
                ss[j] += flip[i][j];
        }
    }
    int s = 0;
    for (int j = 0; j < M; j++)
        s += abs(ss[j]);
    if (s > S)
        S = s;
}

int main()
{
    ifstream in("flip.in");
    ofstream out("flip.out");

    //istream &in = cin;
    //ostream &out = cout;

    in >> N >> M;
    for (int i = 0;i < N; i++)
    {
        for (int j = 0; j < M; j++)
        {
            in >> flip[i][j];
            S += flip[i][j];
        }
    }
    for (long long mask = 1; mask < 1 << N; mask++)
        test(mask);
    out << S;
}