Task: Program Execution
Input (English): 9123, x, 8123, 3733, R, 5501, 2989, 1967, I, J, y, M, R, 5555, 9091, 2425, 7671, 3937, 4343, i, w
Output (English): 2, 5, 9, 10, 11, 12, 13, 20, 21