The task is to generate the correct answer for a given math problem.

Input: Consider Input: Problem: how many prime numbers are between 51 / 13 and 89 / 9 ?

Output: 2


Input: Consider Input: Problem: meena wrote all the numbers from 1 to 29,999 inclusive . how many digits did she write in total ?

Output: 138,889


Input: Consider Input: Problem: if the population of a certain country increases at the rate of one person every 15 seconds , by how many persons does the population increase in 25 minutes ?


Output: 100