Task: Program Execution
Input (English): c, 7, 6, 6, X, 7, t
Output (English): [['c', '7', '6', '6', 'X', '7'], ['c', '7', '6', '6', 'X', 't'], ['c', '7', '6', '6', '7', 't'], ['c', '7', '6', 'X', '7', 't'], ['c', '7', '6', 'X', '7', 't'], ['c', '6', '6', 'X', '7', 't'], ['7', '6', '6', 'X', '7', 't']]