Vector简单实现

#include <iostream>

#include <vector>
const int SPARE_CAPACITY = 20;
template <typename Object>
class Vector
{
private:
    int theSize;
    int theCapacity;
    Object *objects;
public:
    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 Vector & rhs )
    {
        if ( this != &rhs )
        {
            delete [] objects;
            theSize = rhs.size();
            theCapacity = rhs.theCapacity;
            
            objects = new Object [ capacity( ) ];
            for (int k = 0; k < size( ); k++)
            {
                objects[ k ] = rhs.objects[ k ];
            }
        }
        
        return *this;
    }
    
    void resize( int newSize )
    {
        if (newSize >theCapacity ) {
            reserve(newSize * 2 + 1 );
            theSize = newSize;
        }
    }
    void reserve( int newCapacity )
    {
        if ( newCapacity < theSize) {
            return;
        }
        Object *oldArray = objects;
        objects = new Object [ newCapacity ];
        for ( int k = 0; k < theSize; k++) {
            objects[k] =oldArray[k];
            theCapacity = newCapacity;
            delete [] oldArray;
        }
    }
    
    Object & operator[]( int index )
    {
        return objects[index];
    }
    const Object &operator[]( int index ) const
    {
        return objects[ index ];
    }
    bool empty( )const
    {
        return size( ) == 0;
    }
    int size( ) const
    {
        return  theSize;
    }
    int capacity( )const
    {
        return theCapacity;
    }
    void push_back( const Object & x )
    {
        if (theSize == theCapacity ) {
            reserve( 2 *theCapacity + 1 );
        }
        objects[ theSize++ ] = x;
    }
    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() ];
    }

    
    
};