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
# ALMOST PRIME
# Estacio Pereira, estacio.neto@ccc.ufcg.edu.br
# UFCG

# INPUT
number = int(raw_input())

# PROCESS
prime = 0
div = 2
divi = []
num = number
numero = number
almost = 0
while num != 1:
	prime = 0
	div = 2
	divi = []
	while num != 1:
		if not num % div and not div in divi:
			prime += 1
			num /= div
			divi.append(div)
		elif not num % div and div in divi:
			num /= div
		elif num % div:
			div += 1
	numero -= 1
	num = numero
	if prime == 2:
		almost += 1
# OUTPUT
print almost
