记录编号	22140	评测结果	AAATAAAAAA
题目名称	教官	最终得分	90
用户昵称	maxiem	是否通过	未通过
代码语言	Pascal	运行时间	4.278 s
提交时间	2010-11-17 13:24:04	内存使用	0.21 MiB

program officer;
var
  data:array [1..10001] of integer;
  step:array [1..10001] of qword;
  n,i,now:longint;
  a,b,tmp,t:qword;
begin
  assign (input,'officer.in');
  reset (input);
  readln (n);
  for i:=1 to n do readln (data[i]);
  close (input);
  assign (output,'officer.out');
  rewrite (output);
  fillchar (step,sizeof(step),0);
  for i:=1 to n do begin
    now:=data[i];step[i]:=1;
	if now=i then step[i]:=0 else begin
	  while now<>i do begin
	    now:=data[now];
	    step[i]:=step[i]+1;
	  end;
        end;
  end;
  for i:=2 to n do begin
    a:=step[i];b:=step[i-1];
    if a<b then begin
      tmp:=a;
      a:=b;
      b:=tmp;
    end;
    while b>0 do begin
      tmp:=a mod b;
      a:=b;
      b:=tmp;
    end;
    t:=a;
    if step[i]<>0 then step[i]:=step[i] div t*step[i-1] else step[i]:=t;
  end;
  writeln (step[n]);
  close (output);
end.