Task: Program Execution
Input (English): 15, 20, ['N', '9399', 'a', 'L', '8439', 'S', '2003', '1551', '2151', 'g', 'L', '1047', '6543', '6825', '5431', 'o', '9167', 'x', 'y', '3017', '6687', 'U', 'Y', 'g']
Output (English): 5431o9167xy3017