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: 10, 21, ['F', '9123', 'Y', '3669', '2401', '1091', '3429', '5955', 'p', 'u', 'O', '627', 'K', '9221', '5437', 'f', '531', 'x', '2717', 'B', '897', 'r', 'Q', 'j', '6745']

uO627K92215437f531x2717B897