Task: Program Execution
Input (English): Y, 4839, X, 5167, 7263, C, Q, 6133, V, d, 6539, 8585, U, 3109, J, 6131, 2775, 6909, I, 9549, O
Output (English): 1, 3, 6, 7, 9, 10, 13, 15, 19, 21