Task: Program Execution
Input (English): 10, 19, ['X', '6431', 'x', 'C', 'L', '8197', '5031', 'L', 'u', '8643', 'U', 'D', 'w', '2359', 'w', 'z', 'a', 'b', '5571', 'O', '5503', '5291']
Output (English): 8643UDw2359wzab5571