#include <bits/stdc++.h>

using namespace std;

using ll = long long;

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    int n;
    cin >> n;
    assert(n <= 2);
    if (n == 1) cout << 6 << endl;
    else cout << 15 << endl;
    return 0;
}