#include <iostream>
#include <vector>
#include <cstdio>
#include <sstream>
#include <map>
#include <string>
#include <algorithm>
#include <queue>
#include <cmath>
#include <set>
using namespace std;

int main(){
	long long n;
	cin >> n;
	long long ans = 0;
	ans += n/3 + n/5;
	ans *= 2;
	cout << ans << endl;
	return 0;
}