Task: Program Execution
Input (English): 2, 5, ['3969', 'K', 'H', '5639', '1029', '2105', 'O', '1161', 'm', 'A', '5687', 'Y', '6907', '9487', 'Z', '2127', '457', '8673', '509']
Output (English): K, O, Y, 457