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, 8, ['7991', '7999', '8575', '4211', '6003', '2483', '7877', '7249', 'K', '21']

SOLUTION: 94277787384230061124575899971997

PROBLEM: 1, 17, ['1317', '9121', '9155', 'R', 'K', 'N', 'i', '4379', 'g', '7977', '8483', '5501', '3111', '871', '7481', 'h', 'T', 'Y', 'w', '8907', '3839', '1493', 'g', 'I', 'n']

SOLUTION: Th18471781113105538487797g9734iNKR551912197131

PROBLEM: 3, 6, ['K', '3141', '9717', 'O', '535', 'Z']

SOLUTION:
Z535O7179