#include "bits/stdc++.h"
using namespace std;

int main () {
	 ios::sync_with_stdio(false);
	 cin.tie(nullptr);
	 cout.tie(nullptr);
	 int cnt[100000 + 10];
	 for (int i = 1; i <= 100000; ++i) cnt[i] = 0;
	 int n;
	 cin >> n;
	 int remove = 0;
	 for (int i = 1; i <= n; ++i) {
		 int x;
		 cin >> x;
		 if (x > n) {
			 ++remove;
		 } else {
			 cnt[x]++;
		 }
	 }
	 for (int i = 1; i <= n; ++i) {
		 if (i > cnt[i]) {
			 remove += cnt[i];
		 } else {
			 remove += cnt[i] - i;
		 }
	 }
	 cout << remove << '\n';
}