Task: Program Execution
Input (English): F, x, 4163, 5223, B, 9239, u, k, 5517, m, 3443, u, R, 379, X, 3217, 6751, 9131, e, A, 1335, 8103
Output (English): 1, 2, 5, 7, 8, 10, 12, 13, 15, 19, 20