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 Test implements Runnable {
	private void solve() throws IOException {
		int n = nextInt();

		MT timer = new MT();

		int res = 0;
		int cnt,curr;
		for (int t = 1; t <= n; t++) {
			curr=t;
			cnt=0;
			for (int i = 2; i <= curr; i++) {
				if (curr % i == 0) {
					cnt++;
					while (curr % i == 0)
					{
						curr /= i;
					}
				}
			}
			if(cnt==2)
				res++;
		}
		writer.println(res);

		//timer.showTime();
	}

	public static void main(String[] args) {
		new Test().run();
	}

	BufferedReader reader;
	StringTokenizer tokenizer;
	PrintWriter writer;

	public void run() {
		try {
			reader = new BufferedReader(new InputStreamReader(System.in));
			tokenizer = null;
			writer = new PrintWriter(System.out);
			solve();
			reader.close();
			writer.close();
		} catch (Exception e) {
			e.printStackTrace();
			System.exit(1);
		}
	}

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

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

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

	String nextToken() throws IOException {
		while (tokenizer == null || !tokenizer.hasMoreTokens()) {
			tokenizer = new StringTokenizer(reader.readLine());
		}
		return tokenizer.nextToken();
	}

	public class MT {
		long btime;

		MT() {
			btime = System.currentTimeMillis();
		}

		public void showTime() {
			System.out.println("Time = " + (System.currentTimeMillis() - btime)
					+ " ms");
		}
	}
}