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
n = int(input())
def isPrime(k):
    if(k==1):
        return False
    for i in range(2, int(k**0.5)+1):
        if(k%i==0):
            return False
    return True
count = 0
arr = []
for i in range(1, n+1):
    k = i
    div1 = div2 = -1
    for j in range(2, i):
        if(k%j==0):
            if(isPrime(j) and isPrime(k//j) and j!=k//j):
                div1 = j
                div2 = k//j
                #arr.append(k)
                #count+=1
                break
    new_div1, new_div2 = div1, div2 
    pow1 = pow2 = 1
    while(div1>0):
        pow2 = 1
        if(div1**pow1*div2**pow2>n):
            break
        while(True):
            #print(pow1, pow2)
            if(div1**pow1*div2**pow2<=n):
                count+=1
                arr.append(div1**pow1*div2**pow2)
                pow2+=1
            else:
                break
        
        pow1+=1
    '''while(div1>0):
        k = k*div1
        if(k<=n):
            count+=1
        else:
            break
    k = i
    while(div1>0):
        k = k*div2
        if(k<=n):
            count+=1
        else:
            break'''
print(count)