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, 5, ['3155', '5437', '1383', 'L', 'a']
answer:
aL383173455513


question:
4, 7, ['1247', 's', 'J', 'w', 'X', '7211', 'c']
answer:
c1127Xw


question:
15, 15, ['4431', '5185', 'f', '9417', 'q', '9811', '9639', '4781', 'b', 'O', 'z', '4205', '4045', '4903', '7791', 'A', '2269', 'l', '7813', '173', 'b', '8289', 'b', '9041', 'B']
answer:

1977