#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;

int main() {
	int n;
	cin >> n;
	vector<int> p(n);
	for (int i = 0; i < n; i++){
		cin >> p[i];
		p[i]--;
	}
	int ans = 0;
	for (int i = 0; i < n; i++){
		if (p[i] == i){
			continue;
		}
		for (int j = 0; j < n; j++){
			if (p[j] == i){
				swap(p[i], p[j]);
				break;
			}	
		}
		ans++;
	}
	cout << ans << endl;
}