Task: Program Execution
Input (English): 4455, x, t, x, 1837, c, 3579, o, j, u, f, 3723, 6673, a, 4069, q, 2719, 6673, 2747, 9261, 2781, t, x, x
Output (English): a, c, f, j, o, q, t, u, x