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: 15, 16, ['4531', 'a', 'I', 'W', '1071', '1301', 'v', 's', '3521', '7203', '1157', 'w', '7201', 'a', 'I', 'z', 'V', 'X', 'j']

SOLUTION: zI

PROBLEM: 16, 18, ['7121', 'b', 'P', '7771', 'l', 'I', '7817', '5185', '7989', 'H', '4449', '3859', '869', '9321', 'O', '6453', '6219', '8349', '5327', 'm', 'c', 'O', '1185', '2703', '9673', 'q']

SOLUTION: 943891263546

PROBLEM: 4, 4, ['J', '9493', '4491', '6703', '3939', 'q', 'V', 'F', 'U', 'D', 'U', '2273', '321', 'C', '4195', 'l', 'b', 'l', '2571']

SOLUTION:
3076