Task: Program Execution
Input (English): a o h f b 8723 g 3801 o u d 2947 o o 7153 y w x t i 6903 8485 3411 z i e 1671 4051 757 k
Output (English): a, b, d, e, f, g, h, i, k, o, t, u, w, x, y, z