#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
#define FOR(i,a,n) for(int i=a;i<(int)(n);i++)
#define REP(i,n) FOR(i,0,n)
#define ALL(a) (a).begin(),(a).end()
#define MP(a,b) make_pair(a,b)
#define PB(a) push_back(a)
#define F first
#define S second
const int INF = 2000000000;
const int DX[4]={0,1,0,-1}, DY[4]={-1,0,1,0};
struct P{int x;int y;P(int X=0,int Y=0){x=X;y=Y;}};

int main() {
	int N;
	cin >> N;
	map<int,int> m;
	vector<int> v(N);
	REP(i,N) {
		cin >> v[i];
		if(m.find(v[i])==m.end()) m[v[i]] = 1;
		else m[v[i]]++;
	}
	int ans = 0;
	REP(i,N) {
		if(m[v[i]]==1) {
			ans++;
		}
	}
	cout << ans << endl;
	return 0;
}