instruction:
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.
question:
6, 6, ['x', 'o', '4399', '1001', '9267', 'U', 'r', 'e', '6415', '3811', '5385', 'v', 'E', 'q', '6033', 'm', 'i', 'O', 'W', 'R', '4017', 'I', 'T', 'D', '1349', '7213', '9619']
answer:
U


question:
9, 18, ['k', 'p', 'h', 'h', '23', 'j', 'H', '8681', 'P', 'c', '8375', '4243', '8007', 'z', '2155', '9641', 'J', 'k', 'Z']
answer:
kJ14695512z700834245738cP


question:
12, 12, ['c', 'a', 'G', 't', '753', 'x', 'I', '4479', 'i', 'y', 'J', 'w']
answer:

w