Task: Program Execution
Input (English): 18, 20, ['C', 'h', '8975', 'z', 'U', 'U', 'h', '4753', '6569', 's', '821', 'a', '7791', 'O', 'S', '3807', '1883', '427', 'd', '9817', 'F', '4733']
Output (English): 427d9817