#include <iostream>

void solve() {
    int n;
    std::cin >> n;

    int ans = 0;
    for (int t = 0; t * 5 <= n; ++t) {
        for (int g = 0; t * 5 + g * 2 <= n && g <= t; ++g) {
            if ((n - t * 5 - g * 2) % 3 == 0) ++ans;
        }
    }
    std::cout << ans << "\n";
}

int main() {
    std::cin.tie(nullptr);
    std::ios::sync_with_stdio(false);

    solve();

    return 0;
}