program Flip_infoarena;
 type mat = array[1..16,1..16] of longint;
 var a,b: mat;
     n,m: longword;
     i,j: longword;
     f: text;

 function suma_flip(l,c: longint): longword;
 var i,j,s: longword;
 begin

   s:=0;

   for i:=1 to n do
    for j:=1 to m do
      if (i = l) or (j = c) then
         s:=s+(-1)*a[i,j]
      else
         s:=s+a[i,j];

   suma_flip := s;

 end;

 function max: longword;
 var i,j: longword;
     mx: longword;
 begin
    mx:=0;
    for I:=1 to n do
      for j:=1 to m do
        if b[i,j] > mx then mx := b[i,j];
    max:=mx;
 end;

 begin
   assign(f,'flip.in'); reset(f);
     read(f,n,m);
     for i:=1 to n do
       for j:=1 to m do
         read(f,a[i,j]);
   Close(F);

   FillChar(b,sizeof(b),0);

   for i:=1 to n do
     for j:=1 to m do
       b[i,j] := suma_flip(i,j);

   assign(f,'flip.out'); rewrite(f);
     write(f,max);
   Close(F);
 end.