here is code:

    var
      a : array [1..20] of integer;
      y : array [1..2] of integer;
      j, n, min : integer;
   procedure asd(s, x : integer);
     var
       s1, i : integer;

     begin
     i := 1;
     while i <= 2 do
       begin
         if x+1<=n then
           begin
             s1 := abs(s + y[i]*a[x+1]);
             if x+1=n then  begin  if min>s1 then min := s1;  end
             else asd(s1, x+1);
           end
         else inc(i);
         inc(i);
       end;
     end;

begin
  read(n);
  for j := 1 to n do
  read(a[j]);
  min := 100000;
  y[1] := 1;   y[2] := -1;
  asd(a[1], 1);
  writeLn(min);
end.


Can anyone say me where my error is ???

thanks

you have a tremendous error ,and i deem that you are a SB!!

I doubt whether a foreignor can understand what does "SB" mean without knowing about Chinese language.