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

int main(){
	int n;
	cin >> n;
	map<int, int> mp;
	for(int i = 0; i < n; i++){
		int a;
		cin >> a;
		mp[a]++;
	}
	
	int count = 0;
	for(auto x: mp){
		if(x.second == 1){
			count++;
		}
	}
	cout << count << endl;
}