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 concatenate all elements of A from the ith element to the jth element, and print the resultant 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.
Input: 15, 20, ['D', '9187', 'l', 'r', '7655', 'T', 'A', 'O', 'w', 'O', 'G', '6103', 'h', 'S', 'N', '781', 'N', '2803', 'x', 'V', 'O', 'e', 'f']

N781N2803xV