#include <bits/stdc++.h>

#define REP(i, n) for(int = 0 ; i< (int)n; ++i)

using namespace std;

bool testcase(){
	int n;

	if(!(cin >> n))return false;
	
	std::vector<int> perm(n);
	for(int i = 0; i < n; i++)
	{
		std::cin >> perm[i];
		perm[i]--;
	}
	
	std::vector<bool> visited(n);
	int nc = 0;
	for(int i = 0; i < n; i++)
	{
		if(visited[i])
			continue;
		nc++;
		int j = i;
		while(!visited[j])
		{
			visited[j] = true;
			j = perm[j];
		}
	}
	std::cout << n - nc << std::endl;
	return true;
}


int main(){
	while(testcase());
	return 0;
}