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: 6, 7, ['355', '4183', '3563', '8547', '4351', '6841', '5451', 'H', '8035', 'x', '3305', '4233', 'k', '2155', '9987', 'v']

SOLUTION: 15451486

PROBLEM: 1, 4, ['B', '5591', '1237', '1519']

SOLUTION: 915173211955B

PROBLEM: 9, 24, ['R', '841', '8283', 'U', 't', '2549', '3903', 'X', 'y', 'E', 'Y', '1115', '5405', 'u', 'C', '4869', '8813', '9327', '1401', '2251', 'B', 'u', '6507', '7081', '6465']

SOLUTION:
18077056uB15221041723931889684Cu50455111YEy