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:
['6055', 'v', '9455', 'A', '6817', 'D', '9339', 't', 'K', '1993']

Ex Output:
33659


Ex Input:
['Y', '9053', 'N', '6921']

Ex Output:
15974


Ex Input:
['R', '9311', '1397', 'F', 'I', 'T', 't']

Ex Output:

10708