Task: Program Execution
Input (English): 1, 8, ['6431', '2091', 'O', 'b', 'H', 'U', 'I', 'M', 'B', 'n', 'K', '8373', '509', '265', 'O', '3513', '4807', '3481', 'Q', '1287']
Output (English): 6431, B, 4807