数据结构学习（C++）——单链表（定义与实现）[4]

              }

              initialize();

       }

       bool isempty()

       {

              if (first->link == null)

              {

                     initialize();

                     return ture;

              }

              else return false;

       }

      int length() const     //计算带表头节点的单链表长度                                  

       {

              node<type> *p = first->link;

              int count = 0;

              while (p != null)