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, 4, ['B', '5591', '1237', '1519']

SOLUTION: 915173211955B

PROBLEM: 15, 25, ['n', '4163', '6355', '4085', 'u', 'X', '7669', 'c', '791', '7517', '3153', 'k', 'S', '1263', 'P', '1613', 'q', '7693', '339', '7041', '3591', '9429', '4695', '2959', 'm', 'g', '2827', '6699', '1243', 'Y']

SOLUTION: m959259649249195314079333967q3161P

PROBLEM: 1, 2, ['2767', 'H']

SOLUTION:
H7672