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.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.StringTokenizer;

/**
 * @author aneeshashutosh
 */
public class Main {
	public static void main (String[] args) {
		FastReader fr = new FastReader();
		int answer = 0;

		int n = fr.nextInt();
		int[] numPrimeFactors = new int[3001]; // idx is the #, value is # of prime factors
		for (int i = 0; i < n + 1; i++) {
			for (int j = 2; j < i; j++) {
				numPrimeFactors[i] += (numPrimeFactors[j] == 0 && i % j == 0) ? 1 : 0;
			}
			answer += (numPrimeFactors[i] == 2) ? 1 : 0;
		}

		System.out.println(answer);
	}

	private static class FastReader {
		BufferedReader br;
		StringTokenizer st;

		FastReader () {
			br = new BufferedReader(new InputStreamReader(System.in));
		}

		String next () {
			while (st == null || !st.hasMoreElements()) {
				try {
					st = new StringTokenizer(br.readLine());
				} catch (IOException e) {
					e.printStackTrace();
				}
			}
			return st.nextToken();
		}

		int nextInt () {
			return Integer.parseInt(next());
		}
	} // from https://www.geeksforgeeks.org/fast-io-in-java-in-competitive-programming/
}
