Task: Program Execution
Input (English): o, 1387, C, F, k, 8375, Q, 4757, 4883, 7021, S, 8929, T, 4119, 687, 129, 4905, u, 7723, N, 8331, 6515, 9639
Output (English): 1, 3, 4, 5, 7, 11, 13, 18, 20