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.io.PrintWriter;
import java.util.ArrayList;
import java.util.Locale;
import java.util.StringTokenizer;

public class Main implements Runnable {

	private void solve() throws IOException {
		int m = nextInt();
		dime(m);
		int suma = 0;
		for( int i = 1 ; i<=m ; i++ ){
			suma += dime(i);
		}
		out.println(suma);
	}
	//------------------------------------------------
	private int dime(int i) {
		ArrayList<Integer> a = new ArrayList<Integer>();
		if( i==1 ){
			return 0;
			//out.println("NO");
		}
		else{
			boolean b = true;
			while( b==true ){
				int div = 2;
				while(i%div!=0){div++;/*out.println("ahora div es "+div);*/}
				if( i==div ){
					b=false;
					//out.println("a�adi "+div);
					if( a.contains(div)==true ){;}
					else{
						a.add(div);
					}
				}
				else{
					i=i/div;
					//out.println("i ahora vale "+i);
					if( a.contains(div) == true ){
						//out.println("Lo contiene a "+div);
					}
					else{
						a.add(div);
						//out.println("No contiene a "+div);
						//out.println("a�adi "+div);
					}
				}
			}
		}
		if( a.size()==2 ){
			return 1;
		}
		else{
			return 0;
		}		
	}

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

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

	public void run() {
		Locale.setDefault(Locale.US);
		try {
			in = new BufferedReader(new InputStreamReader(System.in));
			out = new PrintWriter(System.out);
			st = new StringTokenizer("");
			solve();
			in.close();
			out.close();
		} catch (Exception e) {
			e.printStackTrace();
			System.exit(566);
		}
	}

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

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

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

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

}
