#include<iostream>
#include<vector>
#include<algorithm>
using namespace std;
int main() {
	int n;
	cin >> n;
	vector<int> a(n);
	for (int i = 0; i < n; i++) {
		cin >> a[i];
	}
	int k = 0;
	sort(a.begin(), a.end());
	if (n>2) {
		for (int i = 1; i < n - 1; i++) {
			if (a[i - 1] != a[i] && a[i] != a[i + 1]) {
				k++;
			}
		}
		if (a[0] != a[1])k++;
		if (a[n - 2] != a[n - 1])k++;
	}
	else if (n == 2) {
		if (a[0] != a[1])k++;
	}
	else {
		k++;
	}
	cout << k << endl;
}