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:
4, 4, ['339', '1345', '9749', '6877', 'b', 'K', 'f', '1443']
answer:
7786


question:
16, 16, ['4793', '8319', 'F', 'L', 'W', 'f', '3003', 'P', 'w', '8231', 'J', 'D', '5091', '5577', 'w', '2211', 'Q', 'a', 'd', '3203', 'v', 'U', '7765', 'S', 'K', '2737', 'R', 'D', 'r', '5487']
answer:
1122


question:
14, 20, ['v', '9673', '1787', 'x', 'f', 'o', '6205', 'F', '2155', '5317', '5129', '9661', 'R', 'X', 'a', 'S', '1549', 'Y', '4743', 'n', 'i', '3045', '6115', '7241', '9045', '83', 'W', 'p', 'o', 'D']
answer:

n3474Y9451SaX