xqueue_print

/********************************************
xqueue_print
ostream & operator<< (ostream & os, const xpoint & x) 
int a; int &ra=a; //定义引用ra,它是变量a的引用，即别名

	friend xpoint operator +(const xpoint & x1, const xpoint & x2);
	friend ostream& operator <<(ostream & os, const xpoint & x);
重载 << cout
	template <class T>
	##Stack<T>& operator =(const Stack<T>& rightSide); 
********************************************/
#include <iostream>
using namespace std;

template <class T>
class xqueue{
public:
	xqueue();
	void enqueue(T item);
	void sort(T *num, int len);
	void print()const;
	xqueue<T>& operator<<(const T & x){
		data[tail] = x;
		tail = (tail + 1) % 10;
		return *this;
	}
	xqueue<T>& operator>>(T & x){
		head = (head + x)%10;
		return *this;
	}

private:
	T data[10];
	int head;
	int tail;
};

template <class T>
xqueue<T>::xqueue():head(0),tail(0){}

template <class T>
void xqueue<T>::enqueue(T item){
	data[tail] = item;
	tail = (tail +1)%10;
}

template <class T>
void xqueue<T>::print()const{
	for(int i = head; i != tail; i=(i+1)%10){
		cout << data[i] << endl;
	}
}



class RN{
public:
	RN(int _x, int _y);
	bool operator>(RN rn)const;
	friend ostream & operator<< (ostream & os, const RN & x);
	void print()const;
private:
	int x;
	int y; 	//x/y
};
RN::RN(int _x = 1, int _y = 1){
	x = _x;
	y = _y;
}
bool RN::operator>(RN rn)const{
	return x/(double)y > rn.x/(double)rn.y;
}
ostream & operator<< (ostream & os, const RN & x){
	os << x.x << "/" << x.y;
	return os;
}



class xpoint{
public:
	xpoint(int _x, int _y);
	bool operator >(xpoint xp)const;
	friend ostream & operator <<(ostream & os, const xpoint & x);
	void print()const;
private:
	int x, y;
};

xpoint::xpoint(int _x = 0, int _y = 0){
	x = _x;
	y = _y;
}

bool xpoint::operator >(xpoint xp)const{
	return (x*x + y*y) > (xp.x*xp.x + xp.y*xp.y);
}

ostream & operator <<(ostream & os, const xpoint & x){
	os << x.x << "," << x.y;
	return os;
}



template <class T>
void print_array(T *buf, int len)
{
	T tmp;
	for(int i = 0; i < len; i++){
		buf[i].print();
	}
}


template <class T>
void xqueue<T>::sort(T *num, int len)  
{  
    int i, j;
	T tmp;
    for(i = 0; i < len; i++){  
	    for(j = 0; j < len - i - 1; j++){  
  
            if(num[j] > num[j + 1]){   //注意是num[j] and num[j + 1]
                tmp = num[j + 1];  
                num[j + 1] = num[j];  
                num[j] = tmp;  
            }  
    	}   
	}  
}


int main(){
	xqueue<RN> q1;
	q1.enqueue(RN(1,2));
	q1.enqueue(RN(4,2));
	q1.enqueue(RN(5,2));
	q1.print();

	xqueue<xpoint> q2;
	q2.enqueue(xpoint(1,8));
	q2.enqueue(xpoint(5,8));
	q2.print();

	xqueue<int> q3;
	q3<<5<<6<<8;
	q3.print();

}

/*$ ./a.out 
1/2
4/2
5/2
1,8
5,8
5
6
8
*/