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, 2, ['5111', 'U', '441', '8381']
answer:
U1115


question:
6, 7, ['E', 'A', 'd', 'a', 'S', '851', '8465', '3205', '5169', '7097', '1679', '3875', 'B', '4761']
answer:
5648158


question:
11, 16, ['m', 'M', '3711', 'V', '1147', 'z', '3577', 'C', '9', 'g', '1007', '345', '879', 'r', 'y', '9171', 'U', 'n', '7731', 'i', 'f', '5659', '3173']
answer:

1719yr9785437001