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: 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: 3, 18, ['R', '7241', 'A', 'z', '8115', '6251', 'F', '1405', 'N', '3567', '1525', 'a', '6057', 'E', '5637', '4969', '3499', '5489', 'Z', 'K', 'M', 'I', 'Z', 'j']

SOLUTION: 9845994396947365E7506a52517653N5041F15265118zA

PROBLEM: 8, 12, ['d', 'k', '731', '9063', '8397', '3225', 'x', 'f', '3619', 'i', '8623', '8861', '69', '2317']

SOLUTION:
16883268i9163f