Task: Program Execution
Input (English): 4, ['2505', '9607', '5233', 'L', '9451', '2819', '3269', '7205', '6345', 'f', '6699', '1359', '2223', 'k', '5173', 'R', 'm']
Output (English): 2505, 9451, 6345, 2223, m