TASK DEFINITION: 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.
PROBLEM: 2, 4, ['U', '4013', '3925', '9017', '3425', 'H', '9015', '4053', '8915', '5945', '8979', '2203']

SOLUTION: 710952933104

PROBLEM: 2, 17, ['4379', 'I', '2897', 't', 'H', 'W', 'z', 'i', 'f', 'b', '2901', '9357', 'c', 'Y', 'R', '2757', 'J', '9265', 'I', 's', 'j', '2617', 'q', 'a']

SOLUTION: J7572RYc75391092bfizWHt7982I

PROBLEM: 10, 15, ['D', '3095', 'a', 't', '9681', 'X', 'O', '6249', '287', 'O', '3427', 'R', '4455', '1021', '5005', '7655']

SOLUTION:
500512015544R7243O