数据结构学习系列二－链表的C++实现

1 先定义一个链表的结构体

（1）包括数据 int data

（2）下一个节点 Node*Next

2 定义一个链表类

#include<iostream>using namespace std;/*单向链表head为头节点，头结点不包含在链表中，所以在计数时不包含头结点*/struct Node{Node*Next;int data;};class NodeManager{private:Node*head;Node*tail;public:NodeManager(){this->head=NULL;this->tail=NULL;}~NodeManager(){while(head){Node*pTemp;pTemp=head;head=head->Next;delete pTemp;}}void AddNode(int data) //添加数{if((head==NULL)&&(tail==NULL)){head=tail=new Node();Node*pNode=new Node();head->Next=pNode;tail->Next=pNode;pNode->data=data;tail=pNode;tail->Next=NULL;}else{Node*pNode=new Node();tail->Next=pNode;pNode->data=data;tail=pNode;tail->Next=NULL;}}void DeleteNode(int dtnum) //删除节点{Node*node=head;//要删除的节点Node*pre=head; //删除的节点的前一个节点while(node!=NULL){if(head==tail)//空链表{return;}if(node->data!=dtnum){pre=node;node=node->Next;}else{if(tail==node){tail=pre;pre->Next=NULL;}else{pre->Next=node->Next;node=pre->Next;//执行下一步}}}}void PrintNode() //打印节点{if(head==NULL){cout<<"此链表为空！"<<endl;return;}Node*node=head->Next;while(node!=NULL){cout<<node->data<<endl;node=node->Next;}}int GetCount()//获取节点的数目{Node*pCurrent=head->Next;//头结点不计int count=0;while(pCurrent!=NULL){count++;pCurrent=pCurrent->Next;}return count;}bool RemoveAt(int index) //删除特定位置的数据{if(index<0||index>getCount()){cout<<"the wrong position!"<<endl;return false;}Node*pre,*cur;pre=head;cur=head->Next;while(index-1){pre=pre->Next;cur=cur->Next;--index;}if(tail==cur){tail=pre;}pre->Next=cur->Next;if(cur!=NULL){return true;}else{return false;}}bool InsertAt(int index,int value)//在索引前插入新节点{if(index<=0||index>this->getCount()){cout<<"the wrong position"<<endl;return false;}Node*current=head;while(index-1){current=current->Next;--index;}Node*add=new Node();add->data=value;add->Next=current->Next;current->Next=add;if(current->Next!=NULL)return true;elsereturn false;}void ClearList() //清空链表{Node*pCurrent1=head;Node*pCurrent2=head;while(pCurrent1->Next){pCurrent2=pCurrent1->Next;delete pCurrent1;pCurrent1=pCurrent2;}head=NULL;}};void main(){NodeManager*nm=new NodeManager();int addnum=0;int dtnum=0;int index=0;int value=0;while(1){char choice;cin>>choice;switch(choice){case '0':return;case '1':cout<<"请输入要添加的数据"<<endl;cin>>addnum;nm->addNode(addnum);cout<<"****************"<<endl;break;case '2':cout<<"显示链表中的数据"<<endl;nm->printNode();cout<<"****************"<<endl;break;case '3':cout<<"请输入要删除的链表中的数据"<<endl;cin>>dtnum;nm->deleteNode(dtnum);cout<<"*****************"<<endl;break;case '4':cout<<"获取链表的长度"<<endl;cout<<nm->getCount()<<endl;cout<<"***************"<<endl;break;case '5':cout<<"按索引删除数据，请输入索引值"<<endl;cin>>index;if(nm->RemoveAt(index)){cout<<"删除数据成功"<<endl;}else{cout<<"删除数据失败"<<endl;}cout<<"****************"<<endl;break;case '6':cout<<"按索引插入值，请输入索引值及要插入的数据"<<endl;cin>>index;cin>>value;if(nm->InsertAt(index,value)){cout<<"插入数据成功"<<endl;}else{cout<<"插入数据失败"<<endl;}cout<<"*******************"<<endl;break;case '7':cout<<"删除链表中的所有数据"<<endl;nm->ClearList();cout<<"*********************"<<endl;break;}}}