var m,n:byte;  
    i,j,max,k:longint;  
    x:array[1..16] of integer;  
    f:text;  
    a:array[1..16,1..16] of longint;  
    procedure inapoi(p:longint);  
   var i,j,e,ee:longint;  
    begin  
   x[p]:=1;  
   if p=n then  
   begin  
   e:=0;  
   for j:=1 to m do  
   begin  
   ee:=a[1,j];  
   for k:=2 to n do  
   ee:=ee+x[k]*a[k,j];  
   e:=e+abs(ee);  
   end;  
   if max<e then max:=e;  
   end  
   else inapoi(p+1);  
   x[p]:=-1;  
   if p=n then  
   begin  
   e:=0;  
   for j:=1 to m do  
   begin  
   ee:=a[1,j];  
   for k:=2 to n do  
   ee:=ee+x[k]*a[k,j];  
   e:=e+abs(ee);  
   end;  
   if max<e then max:=e;  
   end  
   else inapoi(p+1);  
   end;  
   begin  
   assign(f,'flip.in');reset(f);  
   read(f,n);  
   readln(f,m);  
   for i:=1 to n do  
   begin  
  for j:=1 to m do  
 read(f,a[i,j]);  
 readln(f);  
 end;  
  close(f);  
  max:=0;  
   inapoi(1);  
   assign(f,'flip.out');rewrite(f);  
   write(f,max);  
  close(f);  
   end.