#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; 
}