#include <cstdio>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <iostream>
#include <string>
#include <set>
#include <map>
#include <vector>
#include <queue>
#define ll long long
#define db double
using namespace std;
ll n,a[105];
int main() {
	scanf("%lld",&n);
	for (ll i = 1;i <= n;i++) {
		scanf("%lld",&a[i]);
	}
	ll ans = 0;
	for (ll i = 1;i <= n;i++) {
		if (a[i] != i) {
			ll tag = -1;
			for (ll j = i + 1;j <= n;j++) {
				if (a[j] == i) {
					tag = j;
					break;
				}
			}
			a[i] ^= a[tag];
			a[tag] ^= a[i];
			a[i] ^= a[tag];
			ans++;
		}
	}
	printf("%lld",ans);
	return 0;
}