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:
['D', '1693', 'f', 'B', 'o', '3947', '8667', 'f', '6721', '4191', '79']

Ex Output:
25298


Ex Input:
['W', 'H', 'k', 'L', '2425']

Ex Output:
2425


Ex Input:
['u', '5461', '6759']

Ex Output:

12220