#include <cstdlib>
#include <stdio.h>
#include <unordered_set>


int a[30000];
std::unordered_set<int> ok;


int main()
{
  int n, foo, moves, act;

  while(scanf(" %d", &n) == 1) {
    for (int i = 1; i <= n; i++) {
      scanf(" %d", &(a[i]));
      if (a[i] != i) ok.insert(i);
    }
    

    moves = 0;
    // while there are elements to visit:
    while (!ok.empty()){
      
      act = ok.extract(ok.begin()).value();
      foo = act;     

      while (a[foo] != act) {
        foo = a[foo];
        ok.extract(a[foo]);
        moves++;
      } 
    }

    printf("%d\n", moves);
    
  }

  return 0;
}