#include <bits/stdc++.h>

using namespace std;

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

int a[20][20], n, m;
long long s, sum, sol;

int main()
{
    fin>>n>>m;

    for (int i = 0; i < n; i++) for (int j = 0; j < m; j++) fin>>a[i][j], sol += a[i][j];


    for(int k = 0; k < (1<<m); k++)
    {
        sum = 0;
        for(int i = 0; i < n; i++)
        {
            s = 0;
            for(int j = 0; j < m; j++)
            {
                if( ( 1 << j ) & k )
                    s += a[i][j];
                else
                    s -= a[i][j];
            }
            sum += abs(s);
        }
        sol = max(sol, sum);
    }

    fout<<sol;

}