Task: Program Execution
Input (English): S, 7779, 653, 5949, 597, 7897, 9925, t, w, 271, U, 2519, a, Q, 4321, B, v, 8381, u, 5625, 2691, 8717, L
Output (English): 2, 3, 4, 5, 6, 7, 10, 12, 15, 18, 20, 21, 22