Task: Program Execution
Input (English): 4023, 2347, 6925, x, 2037, z, 4685, 7711, S, 8497, t, K, 1257, 4159, B, 1015, 169, u, k, E, y
Output (English): 1, 2, 3, 5, 7, 8, 10, 13, 14, 16, 17