#include <iostream>
using ll = long long;
using namespace std;

int main() {
    ll N;
    cin >> N;
    ll res = N / 15 * 16;
    for(int i=1; i<=N%15; ++i) {
        if(i % 3 == 0 || i % 5 == 0) {
            res += 2;
        }
    }
    cout << res << endl;
}