Instructions: 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.
Input: bruno had some story books . he lost 4 of them and his dad gave him 10 more books . if he had 39 books after that how many books did bruno have at first ?
Output:
33