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:
3, 6, ['6843', '7805', 'h', '9097', 'O', 'u']
answer:
uO7909h


question:
2, 17, ['781', '1949', '8017', 'I', 'F', 'k', 's', 'f', '9531', '3769', '8135', 'R', '7643', 'v', '6217', '4085', 'M', '1993']
answer:
M58047126v3467R531896731359fskFI71089491


question:
2, 20, ['8207', '3191', '6321', '6561', 'K', 'M', '9947', 't', '7157', '1539', 'i', 'O', 'o', '6591', '5381', 'Q', '1185', '5869', '5047', '4267', '467', '4783', 'V', '1073']
answer:

7624740596855811Q18351956oOi93517517t7499MK165612361913