Task: Program Execution
Input (English): 909, 6841, 1607, 2351, f, a, 959, I, 4755, E, f, 6857, 1761, 9307, 3649, 6233, 5767, M, 3733, 9977, b, 707, a
Output (English): 909, 6841, 1607, 2351, 959, 4755, 6857, 1761, 9307, 3649, 6233, 5767, 3733, 9977, 707