#include <fstream>

using namespace std;
int maxx,a[17][17],s,total,t,x,n,m,i,j;
int main()
{
    ifstream fi("flip.in");
    ofstream fo("flip.out");
    fi>>n>>m;
    for(i=1;i<=n;i++)
      for(j=1;j<=m;j++)
        fi>>a[i][j];
    x=(1<<m);
    maxx=-int(2e9);

    for(t=0;t<=x;t++)
    {
      total=0;
      for(i=1;i<=n;i++)
        {
         s=0;
         for(j=1;j<=m;j++)
         if((1<<j)&t) s+=a[i][j]; else s-=a[i][j];
         if(s<-s) s=-s;
         total+=s;
         }
      if(maxx<total) maxx=total;
    }
    fo<<maxx<<"\n";
    fo.close();
    return 0;
}