第八周任务三

/* 实验内容:实现分数类中的运算符重载 
* 程序的版权和版本声明部分  
* Copyright (c) 2011, 烟台大学计算机学院学生  
* All rights reserved.  
* 文件名称：                             
* 作    者：刘杨                              
* 完成日期：2012 年 4 月 11 日  
* 版 本号：  x1.0           
*/

#include<iostream>

using namespace std;

class CFraction
{
private:
	int nume;  // 分子
	int deno;  // 分母
 public:
	CFraction(int nu = 0, int de = 1) : nume(nu), deno(de){};   //构造函数，初始化用
	void output();
	void output1();

	CFraction operator+(CFraction &c1);
	CFraction operator-(CFraction &c1);
	CFraction operator*(CFraction &c1);
	CFraction operator/(CFraction &c1);

	CFraction operator-();//取反

	//比较运算符(二目)的重载
	bool operator > (CFraction &c1);
	bool operator < (CFraction &c1);
	bool operator >= (CFraction &c1);
	bool operator <= (CFraction &c1);
	bool operator == (CFraction &c1);
	bool operator != (CFraction &c1);

};

CFraction CFraction :: operator+(CFraction &c1)
{ 
	CFraction c2;  
    c2.deno = deno * c1.deno;  
    c2.nume = nume * c1.deno + c1.nume * deno;  
    return c2;  
}  

CFraction CFraction :: operator-(CFraction &c1)
{  
	CFraction c2;  
    c2.deno = deno * c1.deno;  
    c2.nume = nume * c1.deno - c1.nume * deno;  
    return c2;  
}  

CFraction CFraction :: operator*(CFraction &c1)
{  
	CFraction c2;  
    c2.deno = deno * c1.deno;  
    c2.nume = nume * c1.nume;  
    return c2;  
}  

CFraction CFraction :: operator/(CFraction &c1)
{  
	CFraction c2;  
    c2.deno = deno * c1.nume;  
    c2.nume = nume * c1.deno;  
    return c2;  
}  

CFraction CFraction :: operator-()//取反
{
	CFraction c2; 
	c2.nume = -nume;
	c2.deno = deno;
    return c2;
}

void CFraction :: output()  
{  
	int i;  
    if(deno == 0)  
    cout<<"error"<<endl; 
	if(nume >= 0)
	{
		if(deno < nume)i = deno;
	    else i = nume;
	    for(; i > 0; --i)
	    {
			if(nume % i == 0 && deno % i == 0)
		    {
				nume = nume / i;
			    deno = deno / i;
			    break;
	        }
         }
	     cout << nume << "/" << deno << endl; 
	}
	else 
	{
		nume = -nume;
		if(deno < nume)i = deno;
	    else i = nume;
	    for(; i > 0; --i)
	    {
			if(nume % i == 0 && deno % i == 0)
		    {
				nume = nume / i;
			    deno = deno / i;
			    break;
	        }
         }
	     cout << -nume << "/" << deno << endl; 
	}
}  

void CFraction :: output1()  
{  
	cout << nume << "/" << deno << endl;  
} 

//比较运算符(二目)的重载
bool CFraction :: operator > (CFraction &c1)
{
	CFraction c2, c3;
	c2.nume = nume * c1.deno;
	c3.nume = c1.nume * deno;
	if(c2.nume > c3.nume)return true;
	else return false;
}

bool CFraction :: operator < (CFraction &c1)
{
	CFraction c2, c3;
	c2.nume = nume * c1.deno;
	c3.nume = c1.nume * deno;
	if(c2.nume < c3.nume)return true;
	else return false;
}

bool CFraction :: operator >= (CFraction &c1)
{
	CFraction c2, c3;
	c2.nume = nume * c1.deno;
	c3.nume = c1.nume * deno;
	if(c2.nume < c3.nume)return false;
	else return true;
}

bool CFraction :: operator <= (CFraction &c1)
{
	CFraction c2, c3;
	c2.nume = nume * c1.deno;
	c3.nume = c1.nume * deno;
	if(c2.nume > c3.nume)return false;
	else return true;
}

bool CFraction :: operator == (CFraction &c1)
{
	CFraction c2, c3;
	c2.nume = nume * c1.deno;
	c3.nume = c1.nume * deno;
	if((c2.nume >= c3.nume) && (c2.nume <= c3.nume))return true;
	else return false;
}

bool CFraction :: operator != (CFraction &c1)
{
	CFraction c2, c3;
	c2.nume = nume * c1.deno;
	c3.nume = c1.nume * deno;
	if((c2.nume > c3.nume) || (c2.nume < c3.nume))return true;
	else return false;
}

void main()
{
	CFraction c1(3, 6), c2(1,4), c3;
	c1.output1();
	c2.output1();

	c3 = c1 + c2;
	cout << "c1 + c2 = ";
	c3.output();
    
	c3 = c1 - c2;
	cout << "c1 - c2 = ";
	c3.output();

	c3 = c1 * c2;
	cout << "c1 * c2 = ";
	c3.output();

	c3 = c1 / c2;
	cout << "c1 / c2 = ";
	c3.output();

	c3 = -c1;
	cout << "-c1 = ";
	c3.output();

	cout << endl;
	
	cout<<"下面比较两个分数的大小：\n";
	if (c1 > c2) cout << "c1 > c2" << endl;
	if (c1 < c2) cout << "c1 < c2" << endl;
	if (c1 == c2) cout << "c1 ＝ c2" << endl; 
	if (c1 != c2) cout << "c1 ≠ c2" << endl;
	if (c1 >= c2) cout << "c1 ≥ c2" << endl;
	if (c1 <= c2) cout << "c1 ≤ c2" << endl;
	cout<<endl;
    system("pause");
}

运行结果：