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 Input:
3, 9, ['R', 'r', '7889', '4141', '1281', 'x', '9299', '4803', 'k', '2433']

Ex Output:
k30849929x182114149887


Ex Input:
7, 18, ['4879', '857', 'X', '8629', 'K', 'l', 'U', '5611', '5989', '4439', '4897', 'D', 'p', '8109', 'F', 'a', '4665', 'Q']

Ex Output:
Q5664aF9018pD7984934498951165U


Ex Input:
1, 6, ['2687', '9771', '1319', 'X', 'r', 't', 'i', 'R', 'v', 'u']

Ex Output:

trX913117797862