Task: Program Execution
Input (English): Q, 1, U, P, x
Output (English): [['Q', '1', 'U', 'P'], ['Q', '1', 'U', 'x'], ['Q', '1', 'P', 'x'], ['Q', 'U', 'P', 'x'], ['1', 'U', 'P', 'x']]