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:
2, 6, ['415', '3603', 'l', 'C', '9471', 'z', '4087', 'Y', 's']
answer:
z1749Cl3063


question:
4, 4, ['u', 'Z', 'e', '253', '2663', 'q', '8421', '2509', '2831', 'H']
answer:
352


question:
1, 2, ['x', 'F', 'U']
answer:

Fx