#include<iostream>
#include<algorithm>
#include <vector>
#include<cmath>
#include<iomanip>
using namespace std;
typedef long long int lont;
int main() {
	int N;
	cin >> N;
	vector<int>veca(N);
	for (int ia = 0; ia < N; ia++) {
		cin >> veca.at(ia);
	}
	sort(veca.begin(), veca.end());
	if (N == 1) {
		cout << 1 << endl;
	}
	else if (N == 2) {
		if (veca.at(0) == veca.at(1)) {
			cout << 0 << endl;
		}
		else {
			cout << 2 << endl;
		}
	}
	else {
		int cnta = 0;
		if (veca.at(0) != veca.at(1)) {
			cnta++;
		}
		if (veca.at(N - 2) != veca.at(N - 1)) {
			cnta++;
		}
		for (int ib = 1; ib < N - 1; ib++) {
			if (veca.at(ib - 1) != veca.at(ib) && veca.at(ib) != veca.at(ib + 1)) {
				cnta++;
			}
		}
		cout << cnta << endl;
	}
}