krsu 5452

/*
by: senb1 aka amigo
*/

#include <bits/stdc++.h>

#define ll long long
#define ull unsigned long long
#define all(x) x.begin(), x.end()
#define fr first
#define sc second
#define mk make_pair
#define rall(x) x.rbegin(), x.rend()
#define endl '\n'

using namespace std;

const ll mod = 998244353;
const ll maxn = 1e7 + 5;
const ll inf = 1e9 + 6;

void solve() {
    int n;
    cin >> n;
    set<int> st;
    for (int i = 0; i < n; i++) {
        int x;
        cin >> x;
        st.insert(x);
    }
    cout << st.size() << endl;
}
/*

*/

int main() {
    ios::sync_with_stdio(0);
    cin.tie(0);

    int t = 1;
    // cin >> t;
    while (t--)
        solve();
}