#include <bits/stdc++.h>

using namespace std;

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

long long n,m,mask,v[17][17],mx;

int main()
{
    in>>n>>m;
    for(int i = 1;i<=n;i++)
        for(int j = 1;j<=m;j++)
            in>>v[i][j];
    for(int mask = 0;mask < (1<<n);mask++)
    {
        long long s[m+1] = {0},p;
        for(int i = 0;(1<<i) <= mask;i++)
        {
            p = 1;
            if(((1<<i) & mask) != 0)
                p = -1;
            for(int j = 1;j<=m;j++)
                s[j] += v[i+1][j]*p;
        }
        long long c = 0;
        for(int i = 1;i<=m;i++)
            c += max(s[i], -s[i]);
        mx = max(mx, c);
    }
    out<<mx;

    return 0;
}