In this task, you are given an input list A. You need to find all the elements of the list that are numbers and calculate their sum.

Ex Input:
['s', '425', '6135']

Ex Output:
6560


Ex Input:
['6731', 'f', '4561', '5601', 'i']

Ex Output:
16893


Ex Input:
['8817', 'l', '1449', 'N', 'k', 'N', 'J', '7551', '5919', 'u', '1967', 'S', '551', '771', '4839']

Ex Output:

31864