#include <iostream>
using namespace std;
using ll = long long;
int main()
{
    ll N;
    cin >> N;
    cout << (N >= 26 ? 8 : N == 9 ? 7 : N == 10 ? 7 : N == 15 ? 7 : N == 16 ? 7 : N == 21 ? 19 : N == 22 ? 7 : N == 25 ? 23 : N - 1) << endl;
    return 0;
}