import java.util.Scanner;

public class Main {
	public static void main(String[] args) {
		Scanner scan = new Scanner(System.in);
		long N = scan.nextLong();
		scan.close();
		long cnt1 = N / 15;
		long cnt2 = N / 3 - cnt1;
		long cnt3 = N / 5 - cnt1;
		long ans = 4 * cnt1 + 2 * (cnt2 + cnt3);
		System.out.println(ans);
	}
}