Task: Program Execution
Input (English): Y, 7685, s, 4401, u, P, p, O, M, 6833, F, 1043, s, 6231, Y, 5795, 6277, g, 8407, k, R
Output (English): 1, 3, 5, 6, 7, 8, 9, 11, 13, 15, 18, 20, 21