Task: Program Execution
Input (English): 4, ['n', 'H', 'O', '9537', '9733', 'f', 'q', '9309', 'H', '3599', '9213', 'h', '1391', 'X', '8371', '5557', '9813', '5863', '6495', 'P']
Output (English): n, H, O, 9537