数据结构-【链表】单向链表的逆置和双向循环链表

单向链表的逆置

1、为什么不能用auto变量的地址去初始化static型指针？
因为Static是在编译时进行初始化的,而Auto是在运行时初始化的,在编译时,Auto变量还不存在呢,当然也就没有地址,初始化就不能成功了.

#include <iostream>using namespace std;typedef struct student{int number;struct student *pNext;} Stu;void create_list(Stu **head)  //创建链表；{Stu *pend=NULL;int id;cout<<"请输入学生的ID，以0结束："<<endl;cin>>id;while(id != 0){Stu *ps=new Stu;ps->pNext=NULL;ps->number=id;if(!(*head)){*head=ps;pend=ps;}else{pend->pNext=ps;pend=ps;}cout<<"请输入学号ID，以0结束:"<<endl;cin>>id;}}void reverse_list(Stu **head)//翻转链表{Stu *pp=NULL;Stu *pNewHead=NULL;if(!(*head)){cout<<"the list is NULL!"<<endl;return ;}while(*head){pp=*head;(*head)=(*head)->pNext;if(!pNewHead){pNewHead=pp;pp->pNext=NULL;//一下把所有的链表的后面都赋空值了；}else{pp->pNext=pNewHead;pNewHead=pp;}}*head=pNewHead;}void show_list(Stu *head){Stu *p=head;while(p){cout<<p->number<<" ";p=p->pNext;}cout<<endl;}void DestoryList(student *head)  //释放内存；{student *temp=NULL;while(head){temp=head;head=head->pNext;delete temp;}}int main(){Stu *head=NULL;create_list(&head);show_list(head);cout<<endl;reverse_list(&head);//逆置链表show_list(head);delete head;system("pause");return 0;}

运行结果：

双向循环链表
实现代码如下：

#include <iostream>#include "windows.h"using namespace std;typedef struct student{int number;struct student *pre;struct student *next;}stu;stu *pend=NULL;stu *phead=NULL;void Create_List()//创建链表；{stu *ps=NULL;ps=new stu;ps->next=NULL;ps->pre=NULL;cout<<"请输入学生的学号："<<endl;cin>>ps->number;while(ps->number!=0){if(!phead)//空表的插入；{phead=ps;pend=ps;}else{pend->next=ps;ps->pre=pend;pend=ps;}ps=new stu;cout<<"请输入学生的ID号，以结束："<<endl;ps->next=NULL;ps->pre=NULL;cin>>ps->number;} delete ps;pend->next=phead;//连接表头表尾；phead->pre=pend;}void Show_List() //从两个方向遍历；{stu *temp=NULL; //正向遍历；temp=phead;cout<<"从头遍历："<<endl;do   //do{} while (); 先执行在判断，所以刚好可以解决双向链表的打印问题；{if(!temp){cout<<"the list is NULL!"<<endl;return ;}cout<<temp->number;temp=temp->next;}while(temp!=phead);cout<<endl;temp=pend;  //反向遍历；cout<<"从尾遍历："<<endl;do{if(!temp){cout<<"the list is NULL!"<<endl;return ;}cout<<temp->number;temp=temp->pre;}while(temp!=pend);cout<<endl;}void Insert_List()  //插入数据；{stu *ps=new stu;stu *temp=NULL;stu *bj=NULL;ps->pre=NULL;ps->next=NULL;cout<<"请输入你要插入的学号："<<endl;cin>>ps->number;if(!phead){phead=ps;cout<<"链表为空，插入成功！"<<endl;return ;}else{if(phead->number > ps->number)//插入的数据在表头；{ps->next=phead;ps->pre=phead->pre;pend->next=ps;phead->pre=ps;phead=ps;cout<<"插入在表头！"<<endl;return;}else{bj=phead;while(bj->next!=phead){if(bj->next->number > ps->number) //在表的中间插入；{ps->next=bj->next;bj->next->pre=ps;ps->pre=bj;bj->next=ps;cout<<"成功插入在链表的中间！"<<endl;return ;}bj=bj->next;}}}}void Delete_List(){stu *temp=NULL;stu *bj=NULL;int id;cout<<"请输入你要删除的学号："<<endl;cin>>id;if(!phead){cout<<"the list is null!"<<endl;return;}else{if(phead->number==id){temp=phead;phead=phead->next;phead->pre=pend;pend->next=phead;delete temp;cout<<"成功删除在头结点"<<endl;return;}else{bj=phead;while(bj->next != phead){if(bj->next->number==id){temp=bj->next;temp->next->pre=bj;bj->next=temp->next;delete temp;cout<<"成功删除在链表的中间位置！"<<endl;return;}}}}}void Search_List(){int id;stu *temp=NULL;stu *bj=NULL;cout<<"请输入你要查询的学生的学号："<<endl;cin>>id;if(!phead){cout<<"the list is null!"<<endl;return;}else{if(phead->number==id){cout<<"查找成功，位置在表头！"<<endl;cout<<phead->number<<endl;return;}else{bj=phead;while(bj->next!=phead){if(bj->next->number == id){cout<<"查找成功，位置在表中！"<<endl;cout<<bj->next->number<<endl;return;}bj=bj->next;}}}cout<<"该信息不存在！"<<endl;}void Update_List(){stu *bj=new stu;int oldid,newid;cout<<"请输入你要修改的学号和新的学号："<<endl;cin>>oldid>>newid;if(!phead){cout<<"the list is null!"<<endl;return ;}else{if(phead->number==oldid){phead->number=newid;cout<<"学号修改成功，在表头！"<<endl;return;}else{bj=phead;while(bj->next->number==oldid){bj->next->number=newid;cout<<"学号修改成功，在表中！"<<endl;return ;}}}cout<<"该信息不存在！"<<endl;}void menue(){while(1){int choice=0;SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_GREEN);//设置代码输出的颜色代码，green，red，blue；cout<<"请选择你要执行的操作："<<endl<<endl;cout<<"1.创建链表："<<endl;cout<<"2.插入数据："<<endl;cout<<"3.查询数据："<<endl;cout<<"4.更新数据："<<endl;cout<<"5.删除数据："<<endl;cout<<"6.显示数据："<<endl;cout<<"7.退出："<<endl<<endl;cin>>choice;switch(choice){case 1:Create_List();break;case 2:Insert_List();break;case 3:Search_List();break;case 4:Update_List();break;case 5:Delete_List();break;case 6:Show_List();break;case 7:return ;default:cout<<"你正确输入你要执行的操作："<<endl;}}}int main(){menue();system("pause");return 0;}

运行结果：