Given a math word problem, answer the following question. You might need to apply addition or subtraction mathematical operators on the numbers embedded in the text to answer the question and then only report the final numerical answer.

Input: Consider Input: there are 64 pigs in the barn . some more come to join them . now there are 86 pigs . how many pigs came to join them ?

Output: 22

Input: Consider Input: haley collected 9 cans for recycling . if she put 7 cans in 1 bag what 's the difference between the number of recycling cans that haley collected and put in the bag ?

Output: 2

Input: Consider Input: alvin is trying to build a small house in the forest so that he has a place to stay whenever he goes hunting . he started by gathering some wood . according to his blueprint he will need 376 pieces of wood . if his friend gave him 123 pieces and his brother gave him 136 pieces how many more wood does he need to gather ?
Output: 117