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 math
import random
import itertools


import time
def timer(f):
    def tmp(*args, **kwargs):
        t = time.time()
        res = f(*args, **kwargs)
        #print("Время выполнения функции: %f" % (time.time()-t))
        return res

    return tmp

primes = []
for i in range(1, 3001):
    prime = True
    for j in range(2, int(math.sqrt(i))+1):
        if i%j == 0:
            prime = False
    if prime:
        primes.append(i)


@timer
def main(n):
    total = 0
    macht = 0
    for j in range(n+1):
        total = 0
        for i in range(len(primes)):
            if j%primes[i] == 0:
                total+=1

        #print(j, total)
        if total == 3:
            macht+=1

    print(macht)

main(int(input()))