#include <iostream>
#include <map>
using namespace std;

int main(void)
{
	int N, tmp, ans;
	map<int, int> mp;
	cin >> N;
	for(int i = 0; i < N; i++) {
		cin >> tmp;
		mp[tmp] = mp[tmp] + 1;
	}
	for(auto itr = mp.begin(); itr != mp.end(); itr++) {
		if(itr->second == 1) ans++;
	}
	cout << ans << endl;
	return 0;
}