#include<fstream.h>
long n,m,a[17][17],x[17],smax;
ifstream f("flip.in");
ofstream g("flip.out");
void cit()
{int i,j; f>>n>>m; smax=0; for (i=1;i<=n;i++) for (j=1;j<=m;j++) {f>>a[i][j];smax+=a[i][j]; }}
void prelsol()
{long s=0,sc;int i,j;
 for(j=1;j<=m;j++)
	{sc=0;
	 for(i=1;i<=n;i++) if(x[i]) sc-=a[i][j]; else sc+=a[i][j];
	 if(sc<0) sc=-sc;
	 s+=sc;
	} 
 if(smax<s) smax=s;
}
void back(long k)
{int i;
 for(i=0;i<=1;i++)
 {x[k]=i;
  if(k==n) prelsol(); else back (k+1); 
 }	 
}
int main()
{cit(); back(1);
 g<<smax<<'\n';	
 g.close();
 return 0;
}