Task: Program Execution
Input (English): 875, 4335, 4955, x, f, p, 9733, 8571, L, 9489, P, 6377, f, B, 5631, 4493, U, G, 1021, 4987
Output (English): 4, 5, 6, 9, 11, 13, 14, 17, 18