Task: Program Execution
Input (English): 21, 23, ['f', '7973', '2353', '6219', '5427', 'U', '3789', '4411', '9833', '8403', '5901', 'a', '9427', 'k', 'Y', 'p', '799', 'u', 'V', '3055', '5761', 'T', 'Y', '4729']
Output (English): YT5761