#include <iostream>
#include <vector>
using namespace std;
int main(void) {
	int n, a;
	cin >> n;
	vector<int> counter(100100, 0);
	for (int i = 0; i < n; ++i) {
		cin >> a;
		++counter[a];
	}
	int ans = 0;
	for (int i = 0; i < 100100; ++i)
		if (counter[i] == 1) ++ans;

	cout << ans << endl;
	return 0;
}