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

bool func(vector<int> a, int b)
{
	int count = 0;
	for(int e: a) {
		if(e == b) {
			count++;
		}
	}
	if(count == 1) {
		return true;
	}
	return false;
}

int main(void)
{
	int N, tmp, ans = 0;
	cin >> N;
	vector<int> A;
	for(int i = 0; i < N; i++) {
		cin >> tmp;
		A.push_back(tmp);
	}
	for(int a: A) {
		if(func(A, a)) {
			ans++;
		}
	}
	cout << ans << endl;
}