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:
18, 23, ['1833', 'M', '3301', '6669', 'K', '7747', 'c', 's', 'd', '6435', 'x', 'Y', '2879', 'R', 'Q', 'R', 'O', 'M', 's', 'd', 'y', '5379', '647', 's', '6155', 'k']
answer:
7469735ydsM


question:
1, 4, ['3633', 'k', '9685', 't']
answer:
t5869k3363


question:
7, 20, ['197', 'E', 'r', 'U', 'q', 'n', 'x', 'J', '7029', '1763', '309', 'Z', '5423', '2739', '9653', '6841', 'W', '5445', '4909', '9743', 'j', 'M', 'I', '5133']
answer:

347990945445W1486356993723245Z90336719207Jx