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.
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Question: 2, 18, ['8671', 'd', '5109', '1915', 'h', '2777', '3087', '9861', '8597', 'P', '4505', 'j', 'M', 'O', 's', 'Q', '2703', 'X', 'l', 'g', '1801']

Answer: X3072QsOMj5054P7958168978037772h51919015d


Question: 3, 6, ['p', 'H', '2775', '2567', '7787', 'D', '3807', '4817', '5399']

Answer: D787776525772


Question: 2, 3, ['c', 'R', '1269', 'x']

Answer:
9621R