var a:array[1..16,1..16] of longint;
    s,ss,smax,hhh:longint;
    f,g:text;
    k,i,j,n,m:byte;
    x:array[0..16] of byte;
begin
assign (f,'flip.in'); reset (f);
assign (g,'flip.out');rewrite (g);
readln (f,n,m);
for i:=1 to n do begin
    for j:=1 to m do read (f,a[i,j]);
     readln (f);
     end;
k:=1;
while k>0 do begin
  if x[k]<2 then x[k]:=x[k]+1;
  if k=n then begin
   ss:=0;
   for j:= 1 to m do begin
       s:=0;
       for i:=1 to n do begin
         if x[i]=2 then s:=s-a[i,j]
                  else s:=s+a[i,j];
                  end;
         if s<0 then ss:=ss-s
                 else ss:=ss+s;
                 end;
         if ss>smax then smax:=ss;
         while x[k]=2 do begin k:=k-1;
         end;
         end
         else begin
         k:= k+1;
         x[k]:=0;
         end
         end ;
   write (g,smax);
   close (f);
   close (g);
   end.