问题：建立单链表，并对单链表中的数据进行排序。方法：先建立单链表，再利用改良的冒泡法对单链表进行排序，并打印输出。-Issues: the establishment of a single linked list, sort and data in a single linked list. Methods: First, create a single linked list, improved reuse bubbling sin

对冒泡排序进行改进。减少循环次数，降低算法复杂度(Improved bubble sort)