fraction.h

分数类

#ifndef FRACTION
#define FRACTION
#include <iostream.h>
#include "except.h"


class Fraction
{
protected:
	int demo;          //分母
	int numer;         //分子
public:
	Fraction(int n=0,int d=1);               //构造函数

	int getNumer();                          //访问分子函数
	int getDemo();                           //访问分母函数
	Fraction Reduce();                       //约分函数
	Fraction Reciprocal();                   //倒数函数
	void tf(Fraction &f);                    //通分函数

	virtual int digit_number();             //计算数字个数函数
	
	Fraction operator-();                   //重载单目“—”运算符

    //重载流插入流提取运算符

	friend istream & operator>>(istream& input,Fraction& f);
	friend ostream & operator<<(ostream& output,Fraction& f);

	//重载"+" "-" "*" "/" ">" ">=" "<" "<=" "==" "!=" 运算符

    friend const Fraction operator+(const Fraction &f1,const Fraction &f2);
	friend const Fraction operator-(const Fraction &f1,const Fraction &f2);
	friend const Fraction operator*(const Fraction &f1,const Fraction &f2);
	friend const Fraction operator/(const Fraction &f1,const Fraction &f2);
	friend const int operator>(const Fraction &f1,const Fraction &f2);
	friend const int operator>=(const Fraction &f1,const Fraction &f2);
	friend const int operator<(const Fraction &f1,const Fraction &f2);
	friend const int operator<=(const Fraction &f1,const Fraction &f2);
	friend const int operator==(const Fraction &f1,const Fraction &f2);
	friend const int operator!=(const Fraction &f1,const Fraction &f2);

	virtual ~ Fraction() {}	//析构函数

};
#endif