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, ['6627', 'J']

SOLUTION: J7266

PROBLEM: 5, 5, ['m', '1577', '7895', 'l', 'K', '2981', '8677']

SOLUTION: K

PROBLEM: 17, 19, ['z', '7969', '6277', '9227', 'Q', '3903', 'L', 'N', '4867', 'y', 'S', '5609', 'N', '9805', '2437', '8583', '2843', 'r', 'H', '3701']

SOLUTION:
Hr3482