instruction:
In this task, you are given inputs i, j, and A, where i and j are integers and A is a list. You need to find all elements of A from the ith element to the jth element, reverse the order in which they occur, and then concatenate them to output the resultant 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 concatenate the elements and then reverse the string.
question:
2, 4, ['9669', '8783', '8485', 'w', 'U', '4489', '1573', '6015', 'p', '1533', 'X', '3123', 'y', 'X', '4921', 'p', 'K', '9841', '8639', '1953']
answer:
w84858783


question:
10, 13, ['c', '9643', '191', 'N', 'n', '2273', 'a', 'q', 'T', '7775', 'v', 'c', '8889', 'G', '533']
answer:
8889cv7775


question:
20, 21, ['1667', 'l', '1093', '6809', '1493', '9949', '7943', 'b', 'h', 'b', '2681', 'L', 'l', 'K', 'L', '8291', '4381', 'a', 'a', '4873', 'p', '5457', 'C', '5169', '1989']
answer:

p4873