TASK DEFINITION: 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.
PROBLEM: 1, 15, ['5997', '2005', '8529', 'j', 'T', '9729', 'T', 'm', '357', '779', '2253', '725', 'z', '4149', '2913', '8135', 'Q', 'B']

SOLUTION: 31929414z5273522977753mT9279Tj925850027995

PROBLEM: 3, 9, ['R', 'r', '7889', '4141', '1281', 'x', '9299', '4803', 'k', '2433']

SOLUTION: k30849929x182114149887

PROBLEM: 3, 3, ['5819', '3317', '451', '5811']

SOLUTION:
154