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: 3, 21, ['V', '3661', '3743', 'Y', '3179', 'b', '7097', '3031', '5859', '4095', 'D', 'J', '2337', '4259', '2539', 'I', '9659', 'U', 'G', 'Q', '3145', '177', '9839', 'f']

SOLUTION: 5413QGU9569I935295247332JD5904958513037907b9713Y3473

PROBLEM: 2, 2, ['4359', 'G', 'A']

SOLUTION: G

PROBLEM: 3, 4, ['s', 'u', 'r', '9579', 'O', '6199', '9831', 'B', '171', 's', '2135', '2937']

SOLUTION:
9759r