c++实现循环队列

#include<iostream.h>
template<class T>
class SeqQueue
{
 private:
  T *element;
  int size;
  int front,rear;
 public:
  SeqQueue(int size=64);
  ~SeqQueue();
  bool IsEmpty();
  void EnQueue(T x);
  T dequeue();
  T length();
};
template<class T>
SeqQueue<T>::SeqQueue(int size)
{
 this->size=size<64?64:size;
 element=new T[this->size];
 front=rear=0;
}
template<class T>
SeqQueue<T>::~SeqQueue()
{
 delete []element;
}
template<class T>
bool SeqQueue<T>::IsEmpty()
{
 return front==rear;
}
template<class T>
void SeqQueue<T>::EnQueue(T x)
{
 if(front==(rear+1)%size)
 {
  T *temp=element;
  element=new T[size*2];
  int i=front,j=0;
  while(i!=rear)
  {
   element[j]=temp[i];
   i=(i+1)%size;
   j++;
  }
  front=0;
  rear=j;
  size*=2;
 }
 element[rear]=x;
 rear=(rear+1)%size;
}
template<class T>
T SeqQueue<T>::dequeue()
{
 if(!IsEmpty())
 {
  T x=element[front];
  front=(front+1)%size;
  return x;
 }
 throw "空队列！";
}
template<class T>
T SeqQueue<T>::length()
{
 if(!IsEmpty())
 {
  T x=rear-front;
  return x;
 }
 throw "空队列！";
}
int main()
{
 SeqQueue<int> Q;
 int x,y,n,i,len;
 cout<<"请输入队列长度："<<endl;
 cin>>n;
 cout<<"请输入各元素的值："<<endl;
 for(i=0;i<n;i++)
 {
 cin>>x;
 Q.EnQueue(x);
 }
 len=Q.length();
 cout<<"当前有效元素的个数是"<<len<<endl;
    cout<<"对头元素是："<<endl;
 y=Q.dequeue();
 cout<<y;
    return 0;

}