#include <queue>
#include <math.h>
#include <stack>
#include <stdio.h>
#include <iostream>
#include <vector>
#include <iomanip>
#include <string.h>
#include <algorithm>
using namespace std;
#define LL long long
#define ull unsigned long long
const int N = 1e6 + 10;
const int INF = 0x3f3f3f3f; 
int a[N];
int main()
{
	int n; 
	cin >> n;
	int ans = 0;
	for(int i = 0 ; i < n ; i++) 
		cin >> a[i];
	sort(a,a+n);
	for(int i = 0 ; i < n ; i++) 
	{
		if(a[i] == a[i+1])
			continue;
		else
			ans++;
	}
	cout << ans;
	return 0; 
}