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.

[EX Q]: 5, 7, ['B', '7943', 'H', 'E', 'p', 'D', 'L', '625', '2757', '4429', '863', 'z', 'l', 'f', '3467', 'X', '4961', 'T', 'k', '1021', 'T', '2249', 'S', 'D']
[EX A]: LDp

[EX Q]: 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']
[EX A]: Y

[EX Q]: 1, 6, ['6163', '5777', '97', '1041', '2857', '5911']
[EX A]:
1195758214017977753616