import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigInteger;

public class Main {
	public static void main(String[] args) {
		BufferedReader buff = new BufferedReader(new InputStreamReader(System.in));

		try {

			BigInteger count = new BigInteger(buff.readLine());
			BigInteger ans = new BigInteger("0");

			ans = ans.add(count.divide(new BigInteger("3")));
			ans = ans.add(count.divide(new BigInteger("5")));

			System.out.println(ans.multiply(new BigInteger("" + 2)).toString());

		} catch (NumberFormatException e) {
			e.getStackTrace();
		} catch (IOException e) {
			e.getStackTrace();
		} catch (Exception e) {
			e.getStackTrace();
		}
	}
}