Vector类实现（C++）

#pragma once
#define DEFAULT_CAPACITY  10


templateclass Vector
{
private:int _capacity ; T*_elem; int _size;//容量默认为10，指向元素的指针，向量的规模
public: Vector(int c=DEFAULT_CAPACITY) { _elem = new T[_capacity = c]; _size = 0; }//构造函数
		Vector(Vectorconst&V, int lo, int hi) { copyFrom(V._elem, lo, hi); }//向量区间复制
		Vector(T* const A, int lo, int hi) { copyFrom(A, lo, hi); }//数组区间复制
		~Vector() { delete[] _elem; }//析构函数
		Vector(int c, T const&e);//初始化
		void insert(int rank, T e);//给秩为r的元素赋值
		//取出秩为r的元素值
		T& operator[](int rank)const { return _elem[rank]; }//重载操作符[]
		void bubblesort();//排序
		void copyFrom(T* constA,int lo,int hi);//拷贝
		void expand();//向量扩容
		void remove(int lo,int hi);//删除操作
		void remove(int rank);//单元素删除
		void push_back(T e);//后面插入
		T find(T e);//查找返回秩最大的那个
		void deduplicate();//无序向量去重
		void uniqufy();//有序向量去重
		int size() { return _size; }//返回大小
		bool empty() { return _size == 0 ? true : false; }//返回是否为空
};




templateVector::Vector(int c, T const&e)//初始化
{
	_elem = new T[_capacity=c];
	_size = c;
	for (int i = 0; i < c; i++)
	{
		_elem[i] = e;
	}
}




templatevoid Vector::copyFrom(T* const A, int lo, int hi)
{
	_elem = new T[_capacity = 2 * (hi - lo)];//分配空间
	_size = 0;
	while (lo < hi)
		_elem[_size++] = A[lo++];
}




templatevoid Vector::bubblesort()//冒泡排序
{
	int n = _size;
	for (bool sorted = false; sorted = !sorted; n--)
	{
		for (int i = 1; i < n; i++)
		{
			if (_elem[i] < _elem[i - 1])
			{
				swap(_elem[i], _elem[i - 1]);
				sorted = false;
			}
		}
	}
}


templatevoid Vector::expand()
{
	if (_size < _capacity)  //未满无需扩容
		return;
	T*oldelem = _elem; _elem = new T[_capacity <<= 1];//容量翻倍
	for (int i = 0; i < _size; i++)
	{
		_elem[i] = oldelem[i];
	}
	delete[] oldelem;//释放空间
}


templatevoid Vector::insert(int rank, T e)
{
	expand();//有必要即扩容
	for (int i = _size; i > rank; i--)     //自后向前
	{
		_elem[i] = _elem[i - 1];//相继后移
	}
	_elem[rank] = e;			//插入元素
	_size++;					//规模增加
}


templatevoid Vector::remove(int lo,int hi)
{
	if (lo == hi)return;
	for (int i = hi; i < _size; i++)//自谦向后移动位置
		_elem[lo++] = _elem[i];
	_size += lo - hi;				//跟新规模
}


templatevoid Vector::push_back(T e)
{
	expand();				//是否扩容
	_elem[_size] = e;		//向后插入
	_size++;				//更新规模
}


templatevoid Vector::remove(int rank)
{
	return remove(rank, rank + 1);
}


templateT Vector::find(T e)
{
	int n = _size;
	while (--n > -1 && _elem[n] != e);//逆向查找
	return n;					//返回-1代表查找失败
		
}


templatevoid Vector::uniqufy()
{
	int i = 0, j = 0;
	while (++j<_size)				//从前向后向前堆
	{
		if (_elem[i] != _elem[j])
			_elem[++i] = _elem[j];
	}
	_size = ++i;						//更新规模
}


templatevoid Vector::deduplicate()
{
	this->bubblesort();
	
}