var n,m : byte;   
    a : array[1..17,1..17] of longint;   
    b : array[1..17] of boolean;   
    max : longint;   
  
procedure Citeste;   
var Intrare : text;   
    i,j : byte;   
begin  
  assign(Intrare,'flip.in');   
  reset(Intrare);   
  readln(Intrare,n,m);   
  for i:=1 to n do  
   for j:=1 to m do read(Intrare,a[i,j]);   
  close(Intrare);   
end;   
  
procedure Urmatorul;   
var i : byte;   
begin  
  i:=1;   
  while b[i] do begin  
    b[i]:=false;   
    i:=i+1;   
  end;   
  b[i]:=true;   
end;   
  
procedure VerificaSuma;   
var i,j : byte;   
    s,t : longint;   
begin  
  t:=0;   
  for i:=1 to n do begin  
    s:=0;   
    for j:=1 to m do  
     if b[j] then s:=s+a[i,j]   
     else s:=s-a[i,j];   
    if s<0 then t:=t-s   
    else t:=t+s;   
  end;   
  if t>max then max:=t;   
end;   
  
procedure Calculeaza;   
var x,i : longint;   
begin  
  x:=1;   
  for i:=1 to 17 do b[i]:=false;   
  for i:=1 to m do x:=x*2;   
  for i:=1 to x do begin  
    VerificaSuma;   
    Urmatorul;   
  end;   
end;   
  
procedure Scrie;   
var Iesire : text;   
begin  
  assign(Iesire,'flip.out');   
  rewrite(Iesire);   
  write(Iesire,max);   
  close(Iesire);   
end;   
  
begin  
  Citeste;   
  Calculeaza;   
  Scrie;   
end.