数据结构：：模拟STL实现list

注意：在STL里面运用的是空间配置器，但是这次我暂时没有用空间配置器，后面我会带上空间配置器再实现一遍。

#include<iostream>#include<assert.h>using namespace std;template<typename T>struct _ListNode{T _data;_ListNode<T>* _pNext;_ListNode<T>* _pPre;_ListNode(const T& x):_data(x),_pNext(NULL),_pPre(NULL){}};template<typename T, typename Ref,typename Ptr>struct _ListIterator{typedef _ListNode<T> Node;typedef _ListIterator<T,T&,T*> Iterator;typedef _ListIterator<T,Ref,Ptr> Self;Node* _node;_ListIterator(){}_ListIterator(Node* node):_node(node){}bool operator != (const Self& s){return _node != s._node;}bool operator == (const Self& s){return _node == s._node;}//前置加加Self& operator++(){_node = _node->_pNext;return *this;}//后置加加Self operator++(int){Self temp(*this);_node = _node->_pNext;return temp;}Ref operator*(){return _node->_data;  //(*_node)._data;}Ptr operator->(){return &_node->_data;}//前置减减Self& operator--(){_node = _node->_pPre;return *this;}Self operator--(int){Self temp(*this);_node = _node->_pPre;return temp;}};template<typename T>class _List{typedef _ListNode<T> Node;public:typedef _ListIterator<T,T&,T*>  Iterator;typedef _ListIterator<T,const T&,const T*> ConstIterator;public:Node* BuyNode(const T& x){return new Node(x);}_List():_pHead(BuyNode(T()))    //参数可以传一个临时对象{_pHead->_pNext = _pHead;_pHead->_pPre  = _pHead;}//插入数据void Push(const T&x){/*Node* pCur = BuyNode(x);Node* pTail = _pHead->_pNext;pTail->_pNext = pCur;pCur->_pPre = pTail;_pHead->_pNext = pCur;pCur->_pPre = _pHead;*/Insert(End(),x);}//删除数据void Pop(){Erase(--End());}//头插void PushFront(const T& x){Insert(Begin(),x);}//头删void PopFront(){Erase(Begin());}//在特定位置插入一段区间template <typename InputIterator>void Insert(Iterator pos,InputIterator first, InputIterator last){while(first != last){Insert(pos,*first);++first;}}//在特定的位置插入数据Iterator Insert(Iterator pos, const T& x){assert(pos._node);Node* pCur = pos._node;Node* pPre = pos._node->_pPre;Node* temp = new Node(x);pPre->_pNext = temp;temp->_pPre = pPre;pCur->_pPre = temp;temp->_pNext = pCur;return temp;}//删除特定位置的数据Iterator Erase(Iterator pos){assert(pos._node && pos._node != _head);   //判断此位置是否合法并且此位置不等于头节点Node* pCur = pos._node->_pNext;Node* pPre = pos._node->_pPre;pCur->_pPre = pPre;pPre->_pnext = pCur;delete pos._node;return Iterator(pCur);}//const Iterator Begin()const{return _pHead->_pNext;}const Iterator End()const{return _pHead;}Iterator Begin(){return _pHead->_pNext;}Iterator End(){return _pHead;}protected:Node* _pHead;};/***********************测试函数************************///测试插入数据和删除数据void  Test1(){_List<int> l1;l1.Push(1);l1.Push(2);l1.Push(3);l1.Push(4);_List<int>::Iterator it1 = l1.Begin();while(it1 != l1.End()){cout<<*it1<<" ";++it1;}cout<<endl;}//头插头删void Test2(){_List<int> l1;l1.Push(1);l1.Push(2);l1.Push(3);l1.Push(4);l1.PushFront(5);_List<int>::Iterator it1 = l1.Begin();while(it1 != l1.End()){cout<<*it1<<" ";++it1;}cout<<endl;}//在特定的位置插入数据void Test3(){_List<int> l1;l1.Push(1);l1.Push(2);l1.Push(3);l1.Push(4);_List<int>::Iterator it1 = l1.Begin();it1 = l1.Insert(it1,6);   //Insert函数有返回值，所以用迭代器返回while(it1 != l1.End()){cout<<*it1<<" ";++it1;}cout<<endl;}//测试插入一段区间void Test4(){_List<int> l1;l1.Push(1);l1.Push(2);l1.Push(3);l1.Push(4);_List<int> l2;l2.Push(12);l2.Push(22);l2.Push(32);l2.Push(42);_List<int>::Iterator it1 = l1.Begin();l1.Insert(it1,l2.Begin(),l2.End());it1 = l1.Begin();while(it1!= l1.End()){cout<<*it1<<" ";++it1;}cout<<endl;}int main(){Test1();Test2();Test3();Test4();return 0;}