#!/usr/bin/env python
# -*- coding: utf-8 -*-

def main():
    n = int(input())
    
    fizzbuzz = n // 5
    fizz = n // 3 - fizzbuzz
    buzz = n // 5 - fizzbuzz
    
    result = fizzbuzz * 4 + fizz * 2 + buzz * 2
    
    print(result)

if __name__ == '__main__':
    main()