#include <iostream>
#include <cstring>
using namespace std;
#define ERROR "通常错误"
template<typename T>
class Vector
{
public:
Vector();
Vector(int num, T data); //使用num个data初始化
Vector(Vector &other);
~Vector();
T &at(int pos);
bool empty();
bool full();
T &front();
T &back();
int size();
void clear();
void expand();
private:
T *begin; //表首
T *end; //数据尾部后一位， 方便填充新数据
T *last; //容器结尾
};
//无参构造
template<typename T>
Vector<T>::Vector(): begin(nullptr), end(nullptr), last(nullptr)
{
cout << "无参析构" << endl;
}
//有参构造
template<typename T>
Vector<T>::Vector(int num, T data): begin(new T[num])
{
if (num < 0)
{
throw ERROR;
}
//容量为2的倍数
int size = 1;
while (size < num) {
size *= 2;
}
memset(begin, 0, size);
end = begin + size;
last = begin + num -1;
T *temp = begin;
for (int i=0 ; i<num ; i++)
{
*temp = data;
temp ++;
}
cout << "有参析构" << endl;
}
//拷贝构造
template<typename T>
Vector<T>::Vector(Vector &other)
{
if (this != &other)
{
int size = other.last - other.begin +1;
this->begin = new T[size];
this->last = this->begin + size -1;
this->end = this->begin + (other.end - other.begin);
memcpy(this->begin, other.begin, size);
}
cout << "拷贝构造" << endl;
}
//析构函数
template<typename T>
Vector<T>::~Vector()
{
delete [] this->begin;
begin = nullptr;
end = nullptr;
last = nullptr;
cout << "析构函数" << endl;
}
template<typename T>
T &Vector<T>::at(int pos)
{
if (pos < 0 || pos > (this->begin - this->last + 1))
{
cout << "越界" << endl;
return NULL;
}
return *(begin+pos);
}
template<typename T>
bool Vector<T>::empty()
{
return this->begin == this->last;
}
template<typename T>
bool Vector<T>::full()
{
return (this->begin - this->last) == (this->begin - this->end);
}
template<typename T>
T &Vector<T>::front()
{
return *this->begin;
}
template<typename T>
T &Vector<T>::back()
{
return *(this->end);
}
template<typename T>
int Vector<T>::size()
{
return this->end - this->begin;
}
template<typename T>
void Vector<T>::clear()
{
memset(this->begin, 0, (this->last - this->begin));
}
int main()
{
cout << "Hello World!" << endl;
return 0;
}