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())
flag=0
counter=0
counter1=0
flag1=0
if n>5:
    for i in range(6,n+1):
        counter=0
        for i1 in range(2,i//2+1):
            flag=0
            flag1=0
            if i%i1==0:
                flag1=1
                for i2 in range(2,int(i1**0.5)+1):
                    if i1%i2==0:
                        flag=1
                        break
            if flag==0 and flag1==1:
                counter+=1
        if counter==2:
            counter1+=1
    print(counter1)
else:
    print(0)