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

Ex Input:
Problem: the population of a bacteria culture doubles every 2 minutes . approximately how many minutes will it take for the population to grow from 1,000 to 300,000 bacteria

Ex Output:
16


Ex Input:
Problem: a train 140 m long is running at 60 kmph . in how much time wiu it pass a platform 260 m long ?

Ex Output:
24 sec


Ex Input:
Problem: for how many unique pairs of nonnegative integers { a , b } is the equation a ^ 2 - b ^ 2 = 99 true ?

Ex Output:

3