#include <fstream>

using namespace std;

int a[18][18];

int ms(int n,int m){
	                  int i,j,s,sl,smax=0;
	                  unsigned st, l=1<<m;
	                  for (st=0;st<l;++st){
	                  	   s=0;
	                  	   for (i=0;i<n;++i){
	                  	   	 sl=0;
	                  	   	 for (j=0;j<m;++j){
	                  	   	 	  if (st & (1<<j)) 
	                  	   	 	  sl-=a[i][j];
	                  	   	 	  else sl+=a[i][j];
	                  	   	 }
	                  	   	 if (sl<0)  sl=-sl;
	                  	   	 s+=sl;
	                  	   }
	                  	   if (s>smax) smax=s;
	                  }
	                  return smax;
}
int main()
{
	int n,m,i,j;
	ifstream fi("flip.in"); 
	ofstream fo("flip.out");
	fi>>n>>m;
	for (i=0;i<n;++i)
	    for (j=0; j<m;++j) fi>>a[i][j];
	    fi.close();
	    fo<<ms(n,m)<<'\n';
	    fo.close();
	    return 0;
}