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

Ex Output:
7786


Ex Input:
1, 2, ['4211', '3035', '3071', '3941', 'D', '1851']

Ex Output:
53031124


Ex Input:
3, 4, ['F', '7799', 'u', '4971']

Ex Output:

1794u