Task: Program Execution
Input (English): 1231, 627, q, Y, i, t, 2879, P, 6697, L, 4111, 6431, Q, 8205, 8997, 4873, V, 2443, 603, 1521
Output (English): 1, 2, 7, 9, 11, 12, 14, 15, 16, 18, 19, 20