#include <iostream>
#include <fstream>
bool p[17];
using namespace std;
int a[10000][10000],sol,curentsol,i,j,n,m,sum,k,maxim=-99999999,s,t;
int main()
{
    ifstream f("flip.in");
    ofstream g("flip.out");
    f>>n>>m;
    for (i=1;i<=n;i++)
        for (j=1;j<=m;j++)
        f>>a[i][j];
    for (j=1;j<=m;j++)
    {
        for (i=1;i<=n;i++)
        {
            if (p[i]==0) s+=a[i][j];
            else
            {
                s-=a[i][j];
            }
        }
        if (s<0) {s=-s;}
        t+=s;
        if (t>maxim) maxim=t;
    }
    g<<maxim;
    return 0;
}