#include <iostream>
#include <cstring>
using namespace std;

int main(){
	long n;
	cin >> n;
	long FizzBuzz = n/15;
	long Fizz = n/3 - FizzBuzz;
	long Buzz = n/5 - FizzBuzz;

	cout << (Fizz+Buzz)*2 + FizzBuzz*4 << endl;

}