#include <fstream.h>
int a[20][20],d[20],m,n,i,j,k,Max=-10000;
 
int modul (int x)
{
    if (x < 0)
        return -x;
    return x;
}
void suma ()
{
    int suma_col = 0, suma_total = 0;
    for (i=1; i<=m; ++i)
    {
      suma_col = 0;
      for (j=1; j<=n; ++j)
      {
      if (d[j] == 1)
            suma_col += a[j][i];
      else
            suma_col+=  a[j][i] * (-1);
      }
      suma_total += modul(suma_col);
    }
    if (Max < suma_total)
        Max = suma_total;
}
  
void back (int k)
    {
    int t;
    for (t=1; t<=2; ++t)
    {
    d[k] = t;
    if (k < n)
        back (k + 1);
    else
        suma ();
    }
}
  
 
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];
          
back(1);
g<<Max;
f.close();
g.close();
     
return 0;
}