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

Ex Input:
Keith has 20 books . Jason has 21 books . How many books do they have together ?

Ex Output:
41


Ex Input:
Gavin has 23 shirts . 6 are blue the rest are green . How many green shirts does Gavin have ?

Ex Output:
17


Ex Input:
Sara has 10 marbles . She loses 7 . How many marbles will Sara have ?

Ex Output:

3