In this task, you are given inputs 'i', 'j', and A, where 'i' and 'j' are integers and A is a list. A list is shown by two brackets and comma-separated numbers and characters inside, like ['1', '12', 'l']. You need to concatenate all elements of A from the ith element to the jth element, and then reverse the resulting 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 reverse first and then concatenate.
19, 19, ['W', 'B', 'L', 'y', 'u', '735', '2629', 'R', '1099', 'f', '7141', '2631', 'i', '4983', '3807', '6841', 'W', 'J', '7739']