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: 3, 20, ['x', 'S', 's', 'a', '5077', 'D', '3979', 'I', '3129', 'R', '8517', 'r', 'l', 'K', 'N', '9701', '227', 'n', '9385', 'U']

Answer: U5839n7221079NKlr7158R9213I9793D7705as


Question: 2, 2, ['w', '5569', '6229', 'b']

Answer: 9655


Question: 26, 30, ['b', '2219', 'G', 'j', '1083', '4133', 'S', '2057', 'v', 'M', '941', '1017', '67', '171', 'e', '2701', '6413', 'X', '531', 'V', 'c', 'G', 'Q', 'z', '3151', 'K', 'N', '1973', 'R', 'N']

Answer:
NR3791NK