用C++实现STL容器vector

template<class Object>
class Vector
{
public:
	enum {SPARE_CAPACITY = 16};
	explicit Vector(int initsize = 0):theSize(initsize), theCapacity(initsize + SPARE_CAPACITY){objects = new Object[theCapacity];}
	Vector(const Vector & rhs):objects(NULL){
		operator=(rhs);
	}
	~Vector(){delete [] objects;}
	const Vector & operator=(const Object &rhs){
		if (this != &rhs){
			delete [] objects;
			theSize = rhs.size();
			theCapacity = rhs.capacity();
			
			objects = new Object[capacity()];
			for (int i = 0; i < size(); i++){
				objects[i] = rhs.objects[i];
			}
		}
		return *this;
	}
	void resize(int newSize) {
		if (newSize > theCapacity)
			reserve(2 * newSize + 1);
		theSize = newSize;
	}

	void reserve(int capacity){
		if (capacity < theCapacity)
			return;
		Object *oldobject = objects;
		objects = new Object[capacity];
		for (int i = 0; i < theSize; i++)
			objects[i] = oldobject[i];

		theCapacity = capacity;
		delete [] oldobject;
	}

	int capacity()const{
		return theCapacity;
	}
	
	int size() const{
		return theSize;
	}

	Object & operator[](int index){
		return objects[index];
	}
	const Object & operator[](int index) const{
		return objects[index];
	}

	bool empty() const{
		return theSize == 0;
	}

	void push_back(const Object & ob){
		if (theSize == theCapacity)
			reserve(2 * theCapacity + 1);
		objects[theSize++] = ob;
	}
	
	void pop_back(){
		theSize--;
	}

	const Object & back() const{
		return objects[theSize-1];
	}

	typedef Object * iterator;
	typedef const Object * const_iterator;

	iterator begin() {
		return &objects[0];
	}
	const_iterator begin() const{
		return &objects[0];
	}
	
	iterator end(){
		return &objects[size()];
	}
	const_iterator end() const{
		return &objects[size()];
	}
private:
	int theSize;
	int theCapacity;
	Object *objects;
};

#include <iostream>
#include "Vector.h"

using namespace std;
//输出数组内容
template<class Object>
void print(Object  & obj)
{
	for (auto it = obj.begin(); it != obj.end(); it++)
		cout << *it << " ";
	cout << endl;
}

int main()
{
	Vector<int> v;

	v.push_back(1);
	v.push_back(2);
	v.push_back(3);
	v.push_back(4);
	cout << "V: ";
	for (auto it = v.begin(); it != v.end(); it++)
		cout << *it << " ";
	cout << endl;
	cout << "V: ";
	print(v);

	v.pop_back();
	cout << "V: ";
	print(v);

	cout << "the size is " << v.size() << endl;
	cout << "the capacity is " << v.capacity() << endl;
	cout << "the back element is " << v.back() << endl;
	if (v.empty())
		cout << "the vector is empty.\n";
	else
		cout << "the vector is not empty.\n";

	system("pause");
	exit(0);
}