You are given a math word problem and you are supposed to apply multiple mathematical operators like addition, subtraction, multiplication or division on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

Ex Input:
The cafeteria had 86 apples . For lunch they handed out 30 to students and decided to use the rest to make pies . If each pie takes 8 apples , how many pies could they make ?

Ex Output:
7


Ex Input:
Dave bought 12 boxes of chocolate candy and gave 5 to his little brother . If each box has 3 pieces inside it , how many pieces did Dave still have ?

Ex Output:
21


Ex Input:
At lunch a waiter had 7 customers and 5 of them did n't leave a tip . If he got $ 3 each from the ones who did tip , how much money did he earn ?

Ex Output:

6