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 find all elements of A from the ith element to the jth element, reverse the order in which they occur, and then concatenate them to output 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. Perform the operations in order, i.e., do not concatenate the elements and then reverse the string.
Input: 17, 18, ['8043', 'N', '3493', '8561', 'q', 'u', '6219', '159', '4569', 'R', '7169', '2857', 'C', '757', '4947', '9821', 'S', '2509', '511', 'p', '9421']

2509S