#include<stdio.h>
#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<utility>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<functional>
#include<math.h>
#include<random>
#include <bitset>
using namespace std;
#define N (1000000000+7)
//#define N 998244353
#define INF 1e16
typedef long long ll;
typedef pair<int,int> P;
typedef vector<ll> vec;
typedef vector<vec> mat;
 
const int inf = (int)1e9; 

ll Pow(ll x,ll power,ll r){
	ll res = 1;
	ll k = power;
	ll y = x%r;
	while (k) {
		if (k & 1)res = (res*y) % r;
		y = (y%r*y%N) % r;
		k /= 2;
	}
	return res;
}


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