#include <bits/stdc++.h>
#define rep(i,n) for(int i = 0; i < (n); ++i)
#define srep(i,s,t) for (int i = s; i < t; ++i)
#define drep(i,n) for(int i = (n)-1; i >= 0; --i)
using namespace std;
typedef long long int ll;
typedef pair<int,int> P;
#define yn {puts("Yes");}else{puts("No");}
#define MAX_N 200005

int main() {
    int n;
    cin >> n;
    map<int, int> mp;
    rep(i,n){
        int a;
        cin >> a;
        auto itr = mp.find(a);
        if(itr != mp.end()){
            mp[a]++;
        }else{
            mp[a] = 1;
        }
    }

    int ans = 0;

    for(auto itr = mp.begin(); itr != mp.end(); itr++){
        if(itr->second == 1)ans++;
    }

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