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.
6, 18, ['7925', 'Q', '6779', '425', '8043', 'R', 'H', 'n', 'R', '4255', 'G', 'p', '5441', 'M', 'u', '8797', '2863', 'N', 'W', 'l', '7147', 'M', '5575', '7705', '4261', '4563', 'v', '955']