适配器Stack----deque/Vector做空间配置器实现

Stack是STL标准模板库中的一种迭代器，有着”先进后出”的特点。
接下来我们分别用deque(双端链表)和Vector(顺序表)来做为Stack的模板参数（底层模板接口）来实现迭代器Stack
用deque实现Stack，deque是由库自己实现，即我们直接利用deque内部已接实现的代码
源代码：

#pragma once


#include<stdio.h>
#include<deque>
#include<iostream>
using namespace std;

template<class T,class Con = deque<T> >
class Stack
{
public:
    typedef size_t SizeType;
    typedef T ValueType;

public:
    Stack()
    {}

    bool Empty()const
    {
        return _con.empty();
    }

    SizeType Size()const
    {
        return _con.size();
    }

    void Pop()
    {
        _con.pop_back();
    }

    void Push(const ValueType data)
    {
        _con.push_back(data);
    }

    ValueType& Top()
    {
        return _con.back();
    }

    const ValueType& Top()const
    {
        return _con.back();
    }

private:
    Con _con;
};

用自己实现的容器Vector做为底层接口实现Stack，
源代码：

#pragma once

#include<cstring>
#include<iostream>
#include<string>
using namespace std;

//Vector容器的模板类
template<class T>
class Vector
{
public:
    typedef T ValueType;
    typedef ValueType* Iterator;
    typedef size_t SizeType;
    typedef ValueType& reference;
    typedef const ValueType* ConstIterator;

public:
    //构造函数
    Vector():_start(0),_finish(0),_endofstorage(0){}

    //重载构造函数
    Vector(SizeType n,const T& value)
        :_start(new T[n*sizeof(T)])
    {
        for(size_t idx = 0;idx < n; ++idx)
            _start[idx] = value;
        _finish = _start + n;
        _endofstorage = _finish;
    }

    //拷贝构造函数
    Vector(const Vector<T>& v)
    {
        size_t size = (v._finish - v._start);
        size_t capacity = v._endofstorage - v._start; 

        _start = new T[capacity];
        for(size_t idx = 0;idx < size; ++idx)
            _start[idx] = v._start[idx];

        _finish = _start + size;
        _endofstorage = _start+capacity;
        /*_finish = v._finish; _endofstorage = v._endofstorage;*/  //错误：浅拷贝
    }

    //赋值运算符重载
    Vector<T>& operator=(const Vector<T>& v)
    {
        _finish = v._finish;
        CheckCapacity();
        Iterator pTemp = new T[v.capacity()];
        Iterator pre = pTemp;
        if(pTemp != NULL)
            /*memcpy(pTemp,v._start,v.size());*/
            for(size_t idx = 0;idx < v.size(); ++idx)
            pre[idx] = v._start[idx];

        if(_start != NULL)
            delete[] _start;

        _start = pTemp;
        _finish = _start+(v._finish-v._start);
        _endofstorage = _start+capacity();
        return *this;

    }

    //析构函数
    ~Vector()
    {
        if(_start != NULL)
        {
            delete[] _start;
        }
        _finish = _start = _endofstorage = NULL;
    }

    ////////////////////////////////////////
    Iterator Begin()
    {
        return _start;
    }
    /*ConstIterator Begin() const { return _start; }*/

    Iterator End()
    {
        return _finish;
    }
    ConstIterator End() const
    {
        return _finish;
    }

    SizeType size()
    {
        return (End()-Begin());
    }
    SizeType size() const
    {
        return (End()-Begin());
    }

    SizeType capacity()
    {
        return (_endofstorage - _start);
    }
    SizeType capacity()const
    {
        return (_endofstorage - _start);
    }

    bool Empty()
    {
        if(size()==0)
            return true;
        return false;
    }

    ValueType operator[](const size_t index)
    {
        return _start[index];
    }

    reference Front()
    {
        return *Begin();
    }

    reference Front()const
    {
        return *Begin();
    }

    reference Back()
    {
        return *(End()-1);
    }

    reference Back()const
    {
        return *(End()-1);
    }

    //////////////////////////////////
    void PushBack(const T& value)
    {
        CheckCapacity();
        *_finish = value; 
        ++_finish;
    }

    void PopBack()
    {
        if(_start == NULL)
            return;
        --_finish;
    }

    Iterator Insert(Iterator pos,const T& value)
    {
        size_t n = pos-_start;
        size_t m =_finish-pos;
        CheckCapacity();
        Iterator pTemp = End();
        for(size_t idx = 0;idx < m;++idx)
        {
            *pTemp = *(pTemp-1); 
            --pTemp;
        }

        *pTemp= value;
        ++_finish;
        return _start+n;//不能直接返回pos的值，因为可能存在扩容，pos的值可能改变
    }

    Iterator Erase(Iterator pos)
    {
        Iterator pTemp = pos+1;
        while(pTemp != End())
        {
            *(pTemp-1) = *pTemp;
            pTemp++;
        }
        --_finish;
        return pos;
    }

    void Resize(SizeType newsize,const T& value)
    {
        if(newsize < size())
            _finish =_start + newsize;
        else
        {
            size_t size = newsize-(End()-Begin());
            CheckCapacity();
            while(size--)
            {
                *_finish = value;
                _finish++;
                CheckCapacity();//不能只进行一次扩容的判断，在finish++的过程中随时可能超过容量
            }
            _finish = _start+newsize;
        }
    }

    void Assign(SizeType n, const T& data)
    {
        if(n<=size())
        {
            SizeType size = (_finish-_start)-n;
            _finish = _finish - size;

            T* pTemp =_start;
            while(pTemp!=_finish)
            {
                *pTemp = data;
                pTemp++;
            }
        }
        else
        {
            T* pRe = _start;

            while(pRe!=_finish)
            {
                *pRe = data;
                ++pRe;
            }
            CheckCapacity();
            while(_finish!=_start+n)
            {
                *_finish = data;
                _finish++;
                CheckCapacity();
            }
        }
    }

private:
    void  CheckCapacity()
    {
        if(_finish >= _endofstorage)
        {
            size_t capacity = 3+(_endofstorage-_start)*2;
            Iterator pTemp = new T[capacity];

            if(pTemp != NULL)
                memcpy(pTemp,_start,sizeof(T)*size());
            if(NULL != _start)
                delete[] _start;

            _finish = pTemp+size();
            _start = pTemp;
            _endofstorage = _start+capacity;
        }
    }
private:
    Iterator _start ;
    Iterator _finish;
    Iterator _endofstorage;
};

//Stack栈的模板类的实现
template<class T,class Con = Vector<T> >
class Stack
{
public:
    typedef size_t SizeType;
    typedef T ValueType;

public:
    Stack()
    {}

    //判空
    bool Empty()
    {
        return (_con.size()==0);
    }
    void Push(const ValueType data)
    {
        _con.PushBack(data);
    }

    void Pop()
    {
        _con.PopBack();
    }

    SizeType Size()const
    {
        return _con.size();
    }

    ValueType& Top()
    {
        return _con.Back();
    }

    const ValueType& Top()const
    {
        return _con.Back();
    }
private:
    Con _con;
};