#include <fstream>

using namespace std;

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

int a[20][20] , base[20] , n , m , sum , sol ,ans;

int main()
{
    int  i , j;
    f >> n >> m ;
    for(i = 1; i <= n ; ++i){
        for(j = 1 ; j <= m ; ++j){
            f >> a[i][j];
        }
    }

    while (!base[0]){
        i = m ;
        while (base[i] == 1)
        {
            base[i] = 0 ;
            --i;
        }
        base[i] = 1;

        ans = 0;

        for(i = 1 ; i <= n ; ++i){
            sum = 0;
            for(j = 1 ; j <= m ;++j){
                if(base[j] == 1){
                    sum += a[i][j];
                }
                else{
                    sum -= a[i][j];
                }
            }
            if(sum < 0)
                sum = -sum;
            ans += sum;
        }

        sol = max(sol , ans);
    }

    g << sol;

    return 0;
}