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: 9, 21, ['D', 'j', 'T', '91', 'W', '9709', 'H', '1023', '4595', '1241', '917', '383', '7739', 'G', 'I', 'b', '8401', '7941', 'j', '2713', 'K', '2443', 'E', 'B', '1515', '5141', '1221', '993']

SOLUTION: K3172j14971048bIG937738371914215954

PROBLEM: 8, 8, ['n', '9001', 't', 'e', 'W', '2287', 'f', '2735', 'z', '3065', 'J', '5609', 'e', 's', 'F']

SOLUTION: 5372

PROBLEM: 7, 20, ['5585', 'k', 'g', '3977', '2527', 'j', '4827', '995', 'J', 'L', '897', '1095', 'f', '1983', 'M', '9065', '2921', '7325', 'l', '2933', '9199', 'D', '243', 'l', 'j', '581', '9165', '9345', '79', 'M']

SOLUTION:
3392l523712925609M3891f5901798LJ5997284