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 JavaApplication111 {
 
    static FastReader input = new FastReader();
    public static void main(String[] args) {
       
        int n=input.nextInt(),count=0;
        for( int i=2;i<=n;i++){
            int c=0;
            for( int x=2;x<i ; x++){
                if((prime(x)&&i%x==0)){ c++;
                }
            }
            if(c==2)count++;
        }
        System.out.println(count);
       
    }

    public static boolean prime(int n){
        for( int i=2 ; i<=Math.sqrt(n)+1 ; i++){
        if(n%i==0&&n!=i)return false;
        }
        return true;
    }
        
    static class FastReader {
        BufferedReader br;
        StringTokenizer st;
 
        public 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()); }
        double nextDouble(){ return Double.parseDouble(next()); }
    }
}