Task: Program Execution
Input (English): u, H, 4, 2, u, Q, 7
Output (English): [['u', 'H', '4', '2', 'u', 'Q'], ['u', 'H', '4', '2', 'u', '7'], ['u', 'H', '4', '2', 'Q', '7'], ['u', 'H', '4', 'u', 'Q', '7'], ['u', 'H', '2', 'u', 'Q', '7'], ['u', '4', '2', 'u', 'Q', '7'], ['H', '4', '2', 'u', 'Q', '7']]