Task: Program Execution
Input (English): 11, 21, ['U', 'L', '2875', '1507', '5113', '3399', 'q', '867', '9847', 'w', '9065', 'X', '6657', 'w', 'd', 'k', 'C', 'B', '209', '9933', '4049']
Output (English): 94043399902BCkdw7566X5609