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: 18, 21, ['7731', '6997', '6801', '9517', 'C', '1231', 'h', 'e', '121', '4987', '8961', 'j', 'y', 'A', 't', 'e', '3331', 'F', 'S', '8907', '1557', 'a', '2851', 'v', '6725', '3607', 'M', '4235']

15578907SF