instruction:
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.
question:
1, 4, ['B', '5591', '1237', '1519']
answer:
915173211955B


question:
8, 21, ['9847', '3163', 'L', 'E', 's', 'I', 'H', 'e', 'l', '8875', '547', 'F', '4221', '5105', '5409', 'M', '6617', 'Z', 'g', '9257', 'l', 'q', 'p', 'Q', '6755', '265', '9845']
answer:
l7529gZ7166M904550151224F7455788le


question:
2, 8, ['O', '4833', '7055', '9891', '9117', '1571', 'S', 'Z', '7741', 'W', 't']
answer:

ZS17517119198955073384