polynomial.h

用循环链表实现的多项式 包括 运算符及io重载

#ifndef POLYNOMIAL_H
#define POLYNOMIAL_H

#include <iostream>
using namespace std;

class Node{
	friend class CircList;
	friend class Polynomial;//是friend Polynomial 还是friend class Polynomial?
public:
	Node(float c=0,int e=0):coef(c),exp(e),link(0){};
	float &GetCoef(){return coef;};
	int &GetExp(){return exp;};
	Node *GetLink()const{return link;};
private:
	float coef;
	int exp;
	Node *link;
};

class CircList{
public:
	CircList();
	~CircList();
	Node *GetNode();
	void RetNode(Node *x);
	void InsertFront(Node *x);
	void InsertRear(Node *x);
	void DeleteFront();
	void DeleteRear();
	void Delete(Node *x);
	Node * GetFirst()const{return first;};//return first
	Node * GetLast()const{return last;};//return last
private:
	Node *first;
	Node *last;
	static Node *av;

};

class Polynomial{
	friend istream & operator>>(istream &input,Polynomial &p);
	friend ostream & operator<<(ostream &output,const Polynomial &p);
	friend Polynomial operator+(const Polynomial &a,const Polynomial &b);
	friend Polynomial operator-(const Polynomial &a,const Polynomial &b);
	friend Polynomial operator*(const Polynomial &a,const Polynomial &b);
public:
	Polynomial(const int=0);//default constructor
	Polynomial(const Polynomial &p);//copy constructor
	const Polynomial &operator=(const Polynomial &p);//assignment operator
	~Polynomial();//destructor
	void AddTerm(Node *x);
	void DeleteTerm();
//	void SetTerms(int t){Terms = t;};
	int GetTerms()const{return Terms;};
	const CircList&GetCl()const{return cl;};
	float Evaluate(float x);
	
private:
	int Terms;//the number of terms, the head node not included
	CircList cl;
	void Copy(const Polynomial &p);//helper function
	float Calculate(float x,float c,int e);//helper function
	char Compare(int x,int y);//helper function
};

#endif