var m,n,i,j,k,ck,suma,suml,max,t:longint;
    v,cv:array[0..16,1..16] of longint;
    f:array[1..16] of byte;
begin
  assign(input,'flip.in'); reset(input);
  assign(output,'flip.out'); rewrite(output);
  readln(n,m);
    for i:=1 to n do begin
      for j:=1 to m do read(v[i,j]);
      readln;
    end;
  t:=1 shl m; max:=0;
  for k:=0 to t-1 do begin
    ck:=k;
    for i:=1 to m do begin f[i]:=ck mod 2; ck:=ck div 2; v[0,i]:=0;end;
    cv:=v;
    for i:=1 to n do
      for j:=1 to m do
        if f[j]=0 then cv[i,j]:=-cv[i,j];
    suma:=0;
    for i:=1 to n do begin
      suml:=0;
      for j:=1 to m do
        suml:=suml+cv[i,j];
      suma:=suma+abs(suml);
    end;
    if suma>max then max:=suma;
  end;
  write(max);
  close(input); close(output);
end.