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, 7, ['P', 'h', '1443', 'b', 'K', '2641', '3831']
answer:
13831462Kb3441hP


question:
1, 1, ['W', '3467']
answer:
W


question:
1, 8, ['3463', '5191', '1963', '3093', 'K', '7121', 'x', '5747', '5357', 'h', 'j', '7107', '2601', '5745', '8873', '3997']
answer:

7475x1217K3903369119153643