#include <iostream>
#include <vector>
#include <string>
#include <cstring>
#include <math.h>
#include <cmath>
#include <limits.h>
#include <map>
#include <set>
#include <queue>
#include <algorithm>
#include <functional>
#include <stdio.h>
using namespace std;

long long MOD = 1000000007;


int main() {
        
    int ans = 0;
    int N;
    cin >> N;
    map<long long, int> M;
    vector<long long> A(N);
    for ( int i = 0; i < N; i++ ) {
        long long a;
        cin >> a;
        A[i] = a;
        
        if ( !M.count(a) ) {
            M.insert( make_pair(a, 1) );
        }
        else {
            M[a]++;
        }
        
    }
    
    
    for ( auto& a : A ) {
        if ( M[a] == 1 ) { ans++; }
    }
    
    cout << ans << endl;
    
    return 0;
}