#include<iostream>
#include<algorithm>
using namespace std;

int main(){
	int n;
	int a[100000];
	cin >> n;
	for (int i = 0; i < n; i++){
		cin >> a[i];
	}
	if (n == 1){
		cout << "1" << endl;
		return 0;
	}
	sort(a, a + n);
	int c = 0;
	if (a[0] != a[1]) c++;
	if (a[n - 2] != a[n - 1]) c++;
	for (int i = 1; i < n - 1; i++){
		if (a[i] != a[i - 1] &&
			a[i] != a[i + 1])c++;
	}
	cout << c << endl;
}