Task: Program Execution
Input (English): 6, e, e, U, 7
Output (English): [['6', 'e', 'e', 'U'], ['6', 'e', 'e', '7'], ['6', 'e', 'U', '7'], ['6', 'e', 'U', '7'], ['e', 'e', 'U', '7']]