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: 16, 18, ['7121', 'b', 'P', '7771', 'l', 'I', '7817', '5185', '7989', 'H', '4449', '3859', '869', '9321', 'O', '6453', '6219', '8349', '5327', 'm', 'c', 'O', '1185', '2703', '9673', 'q']

Answer: 943891263546


Question: 17, 21, ['5503', '2979', '6307', '633', 'n', '9339', '5829', '5291', '8967', 'i', '9063', '975', 'G', '9187', '3227', 'A', '3487', '8187', 'H', '6097', 'H']

Answer: H7906H78187843


Question: 6, 16, ['8777', 'D', 'N', '6689', 'b', 't', '7265', 't', 'O', '4911', 'm', 'R', 'l', '1509', '7819', '3081', 'w', 'm', 'e', 'd', 'D', 'x', 't', '1685', '1395', '5169', '4669', 'G', 'd']

Answer:
180391879051lRm1194Ot5627t