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

Ex Input:
Nancy 's class is going on a field trip to the zoo . If each van can hold 5 people and there are 12 students and 3 adults going , how many vans will they need ?

Ex Output:
3


Ex Input:
Billy has 62 crayons . 52 are eaten by a hippopotamus . How many crayons will Billy have ?

Ex Output:
10


Ex Input:
Tiffany was playing a video game and had 43 lives . In a hard part of the game she lost 14 lives . If she got 27 more lives in the next level , how many lives would she have ?

Ex Output:

56