Definition: In this task, you are given inputs i,j, and A, where i and j are integers and A is a list. You need to concatenate all elements of A from the ith element to the jth element, and print the resultant string. i and j will be non-negative, and will always have a value less than the length of A. i will always be less than j.
Input: 5, 21, ['D', '7163', 's', 'r', '9863', '1813', '5465', '3551', '8291', '1987', '8097', 'F', 'z', 'j', '6111', 'L', '4051', 's', '3803', '7799', '7391']

9863181354653551829119878097Fzj6111L4051s380377997391