#include <bits/stdc++.h>
using namespace std;

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

int a[20], b[20][20], n, m;
int main()
{
    int i, j, s, smax, stot;
    fin >> n >> m;
    for(i = 1; i <= n; i++)
        fin >> b[i][j];
    smax = stot = -1;
    while(a[0] == 0)
    {
        for(j = 1; j <= n; j++)
        {
            s = 0;
            for(i = 1; i <= m; i++)
                if(a[i] == 0) s += b[i][j];
                else s -= b[i][j];
            smax += abs(s);
        }
        stot = max(smax, stot);
        for(i = m; a[i] == 1; i--)
            a[i] = 0;
        a[i] = 1;
    }
    fout << stot;
    return 0;
}