#include <bits/stdc++.h>
using namespace std;
ifstream fin("flip.in");
ofstream fout("flip.out");
int n, st[25], m, a[18][18], smax;

void Sume()
{
    int i, j, s, sum = 0;
    for(i = 1; i <= n; i++)
    {
        s = 0;
        for(j = 1; j <= m; j++)
            if(st[j] == 0) s += a[i][j];
            else s -= a[i][j];
        if(s < 0) s = -s;
        sum += s;
    }
    smax = max(smax, sum);
}

void Back(int top)
{
    if(top == m + 1) Sume();
    else for(int i = 0; i <= 1; i++)
    {
        st[top] = i;
        Back(top + 1);
    }
}

int main()
{
    int i, j;
    fin >> n >> m;
    for(i = 1; i <= n; i++)
        for(j = 1; j <= m; j++)
            fin >> a[i][j];
    Back(1);
    fout << smax << "\n";
    return 0;
}