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:
['Y', 'X', 'd', 'N', '1877', '2865', 'M', '1249', '9385', 'v', 'o', 'P', 'P', '6029']

Ex Output:
21405


Ex Input:
['N', 'V', 't', 'X', 't', 'M']

Ex Output:
0


Ex Input:
['51', '5337', '7671', 'H', 'T', '9501', '429']

Ex Output:

22989