Definition: In this task, you are given inputs i,j, and A, where i and j are integers and A is a list. You need to list all elements of A from the ith element to the jth element. 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.
Input: 12, 13, ['2987', '3195', 'X', '877', 'r', 'x', '4377', 's', '3663', 'r', 'p', 'n', 'x', 'U', '221']

n, x