Task: Program Execution
Input (English): x 151 9761 e 3187 i 5209 7977 b 4855 i c 1669 l 2361 1367 5293 a 5205 z 245 x 6303 4361 x u 4781 g
Output (English): a, b, c, e, g, i, l, u, x, z