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: 15, 23, ['Z', 'h', '4813', '7715', '8439', 'K', '9249', 'F', '9871', '6511', '1841', '4613', '5657', '8623', '4613', '8861', 'v', '3809', 'F', '7859', '9527', '4655', 'l', '8455', '4727', 'V', 'I', 'H', '3505', '6039']

SOLUTION: l556472599587F9083v16883164

PROBLEM: 3, 13, ['5123', '411', 'u', 'd', 'j', '2903', 'h', 'Z', 'd', 'r', 'D', '7915', '9293', '343', '5339', 'l', '447']

SOLUTION:
39295197DrdZh3092jdu