Task: Program Execution
Input (English): i, x, 6, k, 5, m, M
Output (English): [['i', 'x', '6', 'k', '5', 'm'], ['i', 'x', '6', 'k', '5', 'M'], ['i', 'x', '6', 'k', 'm', 'M'], ['i', 'x', '6', '5', 'm', 'M'], ['i', 'x', 'k', '5', 'm', 'M'], ['i', '6', 'k', '5', 'm', 'M'], ['x', '6', 'k', '5', 'm', 'M']]