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:
2, 3, ['U', 'U', '5201', '4581', '2943', 'B', 'j']

Ex Output:
1025U


Ex Input:
6, 13, ['a', 't', '3699', 'H', 'c', 'S', '2713', '5419', 'q', '7877', 'q', 'U', '833', '8411', '2003', '5373', 'P', '2913']

Ex Output:
338Uq7787q91453172S


Ex Input:
1, 2, ['513', '3651', 'O']

Ex Output:

1563315