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:
3, 10, ['g', '5155', 'p', '6627', 'W', 'q', '2851', 'm', 's', '7781', 'u', '9739']
answer:
1877sm1582qW7266p


question:
18, 18, ['O', '7845', 'f', '2313', 'f', '9661', 's', 'O', '6009', '6997', 'f', 'T', 'f', '6517', 'E', 'H', 'k', 'Y', 'i', '2839', '1839', '3251', 'H', '1939']
answer:
Y


question:
12, 17, ['k', '4515', 'U', '4375', '3559', '8945', 'Q', 'U', 'H', 'E', '273', 'X', '69', '4275', 'D', '8721', '6733', '7885']
answer:

33761278D572496X