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:
7, 10, ['417', '8131', '7239', '9699', 'z', 'H', 'P', '9349', '4835', '3217', '9899']
answer:
712353849439P


question:
1, 12, ['f', '8665', '6205', 'L', 'y', 'P', '9351', 'k', '1387', '657', 's', 'k']
answer:
ks7567831k1539PyL50265668f


question:
2, 11, ['7817', '6971', '2189', 'g', '903', '111', 'r', 'C', '3053', '7851', '9097', '6217']
answer:

790915873503Cr111309g98121796