A number is called almost prime if it has exactly two distinct prime divisors. For example, numbers 6, 18, 24 are almost prime, while 4, 8, 9, 42 are not. Find the amount of almost prime numbers which are between 1 and n, inclusive.

Input

Input contains one integer number n (1 ≤ n ≤ 3000).

Output

Output the amount of almost prime numbers between 1 and n, inclusive.

Examples

Input

10


Output

2


Input

21


Output

8
import java.io.*;
import java.util.*;

public class A implements Runnable {

	boolean check(int n) {
		int cnt = 0;
		for (int i = 2; i * i <= n; i++) {
			if (n % i == 0) {
				cnt++;
				while (n % i == 0)
					n /= i;
			}
		}
		if (n > 1) cnt++;
		return cnt == 2;
	}

	private void solve() throws IOException {
		int ans = 0;
		int n = nextInt();
		for (int i = 1; i <= n;i ++) {
			if (check(i)) ans++;
		}
		out.println(ans);
	}

	public static void main(String[] args) {
		new Thread(new A()).start();
	}

	BufferedReader br;
	StringTokenizer st;
	PrintWriter out;
	boolean eof = false;

	public void run() {
		Locale.setDefault(Locale.US);
		try {
			br = new BufferedReader(new InputStreamReader(System.in));
			out = new PrintWriter(System.out);
			solve();
			out.close();
		} catch (Throwable e) {
			e.printStackTrace();
			System.exit(239);
		}
	}

	String nextToken() {
		while (st == null || !st.hasMoreTokens()) {
			try {
				st = new StringTokenizer(br.readLine());
			} catch (Exception e) {
				eof = true;
				return "0";
			}
		}
		return st.nextToken();
	}

	int nextInt() {
		return Integer.parseInt(nextToken());
	}

	long nextLong() {
		return Long.parseLong(nextToken());
	}

	double nextDouble() {
		return Double.parseDouble(nextToken());
	}
}