program aa;
var
ar:array[1..1000] of integer;
l,a,i,j,k:longint;
f:text;
begin
assign(f,'officer.in');
reset(f);
readln(f,a);
for i:=1 to a do
 readln(f,ar[i]);
 for i:=1 to  a do
  if ar[ar[i]]=i  then   begin
  l:=ar[i];
  i:=ar[ar[i]];
  ar[ar[i]]:=l;
  inc(k);
  end;
  for j:=1 to a do
  for i:=1 to a do
   if ar[i]<>i then
   begin
    l:=ar[ar[i]];
 ar[ar[i]]:=ar[i];
  ar[i]:=l;
    inc(k);
    end;
    assign(f,'officer.out') ;
    rewrite(f);
    write(f,k+1);
    close(f);
end.