Task: Program Execution
Input (English): 11, 13, ['2721', 'M', 'B', 'P', 'b', '2815', '7321', '5245', 'A', 'F', 'H', 'x', 'c', 'M', '283', 'i', '2891', '8995', '3377', '3817', '8653']
Output (English): Hxc