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: 1, 2, ['5111', 'U', '441', '8381']

SOLUTION: U1115

PROBLEM: 13, 13, ['o', '1567', '1971', '5659', 'e', '5189', 'a', '617', 'z', 'Q', '1135', '7739', '1689', 't', 'T', 'C', '6001', 'x', '8549', '7189', '3891', 'S', 'Z', '3731']

SOLUTION: 9861

PROBLEM: 2, 9, ['6409', '1975', '1283', '7977', 'W', 'F', '1413', '8381', 'F']

SOLUTION:
F18383141FW779738215791