Task: Program Execution
Input (English): B, m, c, 6, x, o, f
Output (English): [['B', 'm', 'c', '6', 'x', 'o'], ['B', 'm', 'c', '6', 'x', 'f'], ['B', 'm', 'c', '6', 'o', 'f'], ['B', 'm', 'c', 'x', 'o', 'f'], ['B', 'm', '6', 'x', 'o', 'f'], ['B', 'c', '6', 'x', 'o', 'f'], ['m', 'c', '6', 'x', 'o', 'f']]