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.util.*;
import java.io.*;
//Current File Class
public class HELL 
{
    // how to keep reading input from user until endof file
    // are there any built in sort function for all containers
    // how to initialize a size for a vector and fill it with 0
    static Scanner cin=new Scanner(System.in);
    public static void main(String[] args)
    {
        int n=cin.nextInt(),divCntr=0;
        int[] arr=new int[n+1];
        Vector<Integer> v1=new Vector<Integer>();
        for(int j=2;j<arr.length;++j)
        {
            if(arr[j]==0)
            {
                v1.add(j);
                int x=j,temp=j;
                while(x<arr.length)
                {   arr[x]=1;       x=j*temp++;         }
            }
        }
        for(int j=2;j<arr.length;++j)
        {
            int cntr=0;
            for(int i=0;i<v1.size();++i)
            {
                if(v1.elementAt(i)>j || cntr>2)
                    break;
                if(j%v1.elementAt(i)==0 && v1.elementAt(i)!=j)
                    ++cntr;
            }
            divCntr=(cntr==2) ? ++divCntr : divCntr;
        }
        System.out.println(divCntr);
    }
}