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, 7, ['P', 'h', '1443', 'b', 'K', '2641', '3831']

SOLUTION: 13831462Kb3441hP

PROBLEM: 2, 4, ['U', '4013', '3925', '9017', '3425', 'H', '9015', '4053', '8915', '5945', '8979', '2203']

SOLUTION: 710952933104

PROBLEM: 7, 10, ['S', '9659', '6907', '5979', '1785', '6307', '7075', '6269', '2899', 'k', '5919', '5341', 'H', '3807', 't', '5501', '5511', '5229']

SOLUTION:
k998296265707