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
/*
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import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;

/**
 *
 * @author fcocl_000
 */
public class AlmostPrime {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) throws IOException {
        // TODO code application logic here
        
        //crear criba de factorizacion
        int cribSize = 1000000;
        int[] criba = new int[cribSize];
        
        criba[1] = 1;
        int i = 2;

        while(i < cribSize) {
            if (criba[i] != 0) {
                i++;
            }
            else {
                for (int j = 1; j*i < cribSize; j++) {
                    if (criba[j*i] == 0) {
                        criba[j*i] = i;
                    }
                }
                i++;
            }
        }
        
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        int n = Integer.parseInt(reader.readLine());
        int almost = 0;
        
        for (int j = 1; j <= n; j++) {
            ArrayList<Integer> factores = new ArrayList<>();
            int a = j;
            while (a != 1) {
                if (!factores.contains(criba[a])) {
                    factores.add(criba[a]);
                }
                a /= criba[a];
            }
            if (factores.size() == 2) {
                almost++;
            }
        }
        System.out.println(almost);
    }
}