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: 9, 21, ['7903', '9553', 'J', '3439', '6709', '8539', 'Z', 'B', 'B', '455', '5417', 'Q', 'n', 'R', 'k', '639', '6371', 'K', 't', 'W', 'h', '6315']
Output:
B4555417QnRk6396371KtWh