#include <bits/stdc++.h>
using namespace std;
ifstream in("flip.in");
ofstream out("flip.out");
const int N = 20;
int v[N][N],s[N],n,m,rez;
bool flip[N];
void getAns()
{
    int s = 0;
    for (int i = 1; i<=n; i++)
    {
        int s1 = 0, s2 = 0;
        for (int j = 1; j<=m; j++)
        {
            if (flip[j])
            {
                s1+=v[i][j];
                s2-=v[i][j];
            }
            else
            {
                s1-=v[i][j];
                s2+=v[i][j];
            }
        }
        s+=max(s1,s2);
    }
    rez = max(rez,s);
}
void bkt(int k)
{
    if (k == m+1)
    {
        getAns();
        return;
    }
    flip[k] = 1;
    bkt(k+1);
    flip[k] = 0;
    bkt(k+1);
}
int main()
{
    in >> n >> m;
    for (int i = 1; i<=n; i++)
        for (int j = 1; j<=m; j++)
            in >> v[i][j];
    rez = INT_MIN;
    bkt(1);
    out << rez;
}