#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using vll = vector<long long>;

int main() {
    ll n;
    cin>>n;
    unordered_map<ll,ll> mp;
    for(ll i=0;i<n;i++){
        ll j;
        cin>>j;
        if(mp.find(j)==mp.end()){
            mp[j]=1;
        }else{
            mp[j]++;
        }
    }
    ll ans=0;
    for(const auto &i:mp){
        if(i.second==1){
            ans+=1;
        }
    }
    cout<<ans<<endl;

    system("pause");
}