#include <bits/stdc++.h>

using namespace std;
#define ll long long
#define INF 1234567890
#define N 20
typedef vector<int> vi;
typedef pair<int,int> pi;

ifstream fin("flip.in");
ofstream fout("flip.out");
int t[N][N], maxim = -INF, v[N];
int n, m, suma = 0;
int sum()
{
    int rez = 0;
    for(int j = 1; j <= m; ++j)
    {
        int s = 0;
        for(int i = 1; i <= n; ++i) s += t[i][j] * v[i];
        rez += abs(s);
    }
    return rez;
}
void bk(int k)
{
    if(k > n) maxim = max(maxim, sum());else
    {
        v[k] = 1;
        bk(k + 1);
        v[k] = -1;
        bk(k + 1);
    }

}
int main()
{
    ios::sync_with_stdio(false);
    fin.tie(0);
    fin >> n >> m;
    for(int i = 1; i <= n; ++i)
        for(int j = 1; j <= m; ++j) fin >> t[i][j];
    bk(1);
    fout << maxim;
    return 0;
}