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: 4, 15, ['P', 'G', 'm', 'Q', '361', 'Y', 'i', '9021', '5793', '7443', 'R', 'u', '1309', '4045', 'W', '4649', 'W', 'K', 'p', 'c']

W40451309uR744357939021iY361Q