const
  maxN = 100;
  pred : array[1..3]of longint = (3,1,2);
  succ : array[1..3]of longint = (2,3,1);

var
  now,tar : array[0..maxN]of longint;
  ans,n : longint;

  procedure Move(v,whi : longint);
  var i,j,middle : longint;
  begin
    if whi=pred[now[v]] then middle:=succ[now[v]]
                        else middle:=pred[now[v]];
    for i:=v-1 downto 1 do
      if now[i]<>middle then Move(i,middle);
    ans:=ans+1;
    now[v]:=whi;
  end;
var i : integer;
begin
  read(n);
  for i:=1 to N do begin
    read(tar[i]);
    now[i]:=1;
  end;
  for i:=n downto 1 do
    if tar[i]<>now[i] then Move(i,tar[i]);
  writeln(ans);
end.

> 2
> 2
> 1
>
> Good luck !
>
> QH@

I think the answer is 3!
1
2              -->   2          -->       -->     1
3 empty empty        3 empty 1      3 2 1      3  2  empty

What wrong with the answer? Is my comprehesion wrong?