#include <bits/stdc++.h>

using namespace std;

int main(){
    #ifndef ONLINE_JUDGE
    freopen("debug.in", "r", stdin);
    #endif // ONLINE_JUDGE

    int n, one;
    cin >> n;
    one = n / 2 + n % 2;
    if(one % 2 == 0){
        cout << 15;
    } else {
        cout << 16;
    }
    return 0;
}