import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int ans;
		int a;
		int b;
		int c;

		a = n / 15;
		b = n / 5;
		c = n / 3;
		if(a == 0){
			ans = 2 * (b + c);
		}else{
			ans = 4 * a +  2 * ((b - b / 3) + (c - c / 5));
		}
		System.out.println(ans);
	}

}