How difficult it is to be a schoolboy! It is these thoughts that most often visit Petya after mathematics lessons. Today the teacher told me what prime numbers are. Petya heard about them for the first time. It turns out that the prime number — This is a natural number that has exactly two different natural divisors, that is, it is divisible without remainder only by one and by itself. After the lesson, Petya and his friend Seryozha came up with the following game: one calls two numbers A and B, and the other says how many zeros are at the end of the product of all primes between A and B inclusive. Petya noticed that Seryozha answers the question much faster than he does, and asks you to help him. Write a program for Petya that will answer Serezha's questions.
Input
The input is two numbers A, B (1 ≤ A ≤ B ≤ 10
9), separated by a space. It is guaranteed that there is at least one prime number between A and B.
Imprint
Print the number of zeros that ends the product of all prime numbers on the interval from A to B.
Examples
| # |
Input |
Output |
| 1 |
1 7 |
1 |
| 2 |
3 3 |
0 |