#include <fstream>
#define nrmax 18
using namespace std;
ifstream f("flip.in");
ofstream g("flip.out");
int n,m,ans, st[nrmax*nrmax], a[nrmax][nrmax], i, j, sumtot, sumlin = 0;

void suma()
{
    sumtot=0;
        for(i=1; i<=n; i++)
        {
            sumlin = 0 ;
            for(j=1; j<=m; j++)

                sumlin += a[i][j]*st[j];

            if(sumlin < 0 )
            sumlin *= -1;

            sumtot += sumlin;
        }
        if( sumtot > ans)
            ans = sumtot;
}

void bkt(int k)
{
    if( k > n && k > m)
        suma();
    else
    {
        st[k] = 1;
        bkt(k+1);
        st[k] = -1;
        bkt(k+1);

    }
}

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

    return 0;
}