TASK DEFINITION: In this task, you are given inputs i, j, and A, where i and j are integers and A is a list. You need to find all elements of A from the ith element to the jth element, reverse the order in which they occur, and then concatenate them to output the resultant 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 concatenate the elements and then reverse the string.
PROBLEM: 3, 3, ['U', '8399', '645', '3165']

SOLUTION: 645

PROBLEM: 3, 5, ['m', 'U', '3235', 'B', '2015']

SOLUTION: 2015B3235

PROBLEM: 3, 4, ['4029', '9453', '9479', '591']

SOLUTION:
5919479