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: 11, 12, ['n', '8991', 'Z', '4113', '1623', '1351', 'l', 'p', 'T', '9931', '11', 'i', '1775', 'h', '7237', '8553', 'Q', 'U', '5395', '8727']

SOLUTION: i11

PROBLEM: 1, 4, ['t', '6037', 'I', '2769', 'C']

SOLUTION: 9672I7306t

PROBLEM: 2, 3, ['U', 'U', '5201', '4581', '2943', 'B', 'j']

SOLUTION:
1025U