text: insert the following data
code: head = push ( head , 9 ) ; head = push ( head , 3 ) ; head = push ( head , 5 ) ; head = push ( head , 10 ) ; head = push ( head , 12 ) ; head = push ( head , 8 ) ; document . write ( " " ) ; printList ( head ) ; head = insertionSort ( head ) ; document . write ( " " ) ; printList ( head ) ;