#include <stdio.h>
#include <algorithm>
#include <iostream>
#include <string>
#include <vector>
#include <functional>
#include <map>
#include <iomanip>
#include <math.h> 
#include <stack>
#include <queue>
#include <bitset>
#include <cstdlib>
#include <tuple>
#include <cctype>
#include <ctype.h>
#include <set>
#include <sstream>

using namespace std;

int main(){
	int i, j;
	long long n;

	cin >> n;


	long fb = n / 15;
	long f = n / 3;
	long b = n / 5;


	long sum = fb * 4 + (f-fb) * 2 + (b-fb) * 2;
	

	cout << sum << endl;













	getchar();
	getchar();
	return 0;
}