402830: GYM100905 B Amusing numbers

Bulat is fond of mathematics and already has solved a lot of problems. He thought, that he would be able to solve any problem, but his teacher gave him very interesting problem.

Let's call integer n amusing, if two conditions hold:

• n is composite
• Number of divisors of n is a prime number

Now Bulat want's to answer the question: how many amusing numbers are there from l to r, inclusive? This problem seems very difficult for him, so he asks for your help.

Input consists of two integers l and r (1 ≤ l ≤ r ≤ 10¹⁴).

Output single integer: number of amusing number from l to r inclusive.

1 9

2

3 6

1

6 9

1