List（3）List的单链式实现的增强版(保留当前位置)

list.h

/*-----------------------------------------------   Created By EverSteins   Email:[e-mail]  转载请注明出处  ------------------------------------------------*/ typedef int ElemType;typedef struct Node{ElemType entry;Node *next;Node():entry(0),next(NULL){}Node(ElemType entry):entry(entry),next(NULL){}Node(ElemType entry,Node *link=NULL):entry(entry),next(link){}}Node;class List{public:List():count(0),head_node(NULL),current_position(0),current_node(NULL){}//List(const ElemType ©);//void operator=(const ElemType ©);~List();bool insert(int position,const ElemType &x);bool remove(int position,ElemType &x);bool empty() const;void showAll() ;protected:int count;Node *head_node;mutable int current_position;mutable Node *current_node;void set_position(int position) const;};

list.cc

/*-----------------------------------------------   Created By EverSteins   Email:[e-mail]  转载请注明出处  ------------------------------------------------*/ #include "stdafx.h"#include "utility.h"#include "list.h"using namespace std;void List::set_position(int position) const{//pre:0<=position<countif (position<current_position){current_position=0;current_node=head_node;}for (;current_position!=position;current_position++)current_node=current_node->next;}bool List::insert(int position,const ElemType &x){//pre:0<=position<countif (position<0 || position>count)return false;if (position>0){set_position(position-1);Node *old_node=current_node->next;Node *new_node=new Node(x,old_node);current_node->next=new_node;}else{Node *new_node=new Node(x,head_node);head_node=new_node;current_position=0;current_node=head_node;}count++;return true;}bool List::remove(int position,ElemType &x){if (position<0 || position>=count)return false;if (position>0){set_position(position-1);Node *remove_node=current_node->next;Node *remove_following_node=remove_node->next;current_node->next=remove_following_node;x=remove_node->entry;delete remove_node;}else{//todo}count--;return true;}bool List::empty() const{return count<=0;}void List::showAll() {Node *current_node=head_node;while (NULL != current_node){cout<<current_node->entry<<" ";current_node=current_node->next;}}List::~List(){Node *current_node=head_node;while (NULL != current_node){Node *following_node=current_node->next;delete current_node;current_node=following_node;}}

main.cc

/*-----------------------------------------------   Created By EverSteins   Email:[e-mail]  转载请注明出处  ------------------------------------------------*/ #include "stdafx.h"#include "utility.h"#include "list.h"using namespace std;int _tmain(int argc, _TCHAR* argv[]){List list;list.insert(0,0);list.insert(1,10);list.insert(2,20);list.insert(3,30);list.insert(4,40);list.insert(5,50);list.insert(3,-1);list.insert(3,-2);list.insert(3,-3);list.showAll();return 0;}