第八周任务3

#include <iostream>
using namespace std;
class CFraction
{
private:
 int nume;  // 分子
 int deno;  // 分母
public:
 CFraction(){nume=0;deno=0;}
 CFraction(int n,int d) :nume(n),deno(d){}
 CFraction operator +(CFraction &x);
    CFraction operator -(CFraction &x);
    CFraction operator *(CFraction &x);
    CFraction operator /(CFraction &x);
    bool operator >(CFraction &x);
  bool operator <(CFraction &x);   //构造函数及运算符重载的函数声明
    bool operator =(CFraction &x);
    bool operator >=(CFraction &x);
    bool operator <=(CFraction &x);
 bool operator !=(CFraction &x);//死记住开头的形式，
    //CFraction operator-();/////////////////////////////////////////////////
 int f(int,int);
 int g(int,int);
 void display();
};
CFraction CFraction::operator +(CFraction &x)
{   
 CFraction c;

 int t=f(deno,x.deno);
 c.nume=nume*(t/deno)+(t/x.deno)*x.nume;
 c.deno=t;
    t=g(c.nume,c.deno);
 c.nume=c.nume/t;
 c.deno=c.deno/t;
 return c;

}
CFraction CFraction::operator -(CFraction &x)
{   
 CFraction c;

 int t=f(deno,x.deno);
 c.nume=nume*(t/deno)-(t/x.deno)*x.nume;
 c.deno=t;
    t=g(c.nume,c.deno);
 c.nume=c.nume/t;
 c.deno=c.deno/t;
 return c;
}



CFraction CFraction::operator *(CFraction &x)
{
 CFraction c;
 int t;
 c.nume=nume*x.nume;
 c.deno=deno*x.deno;
 t=g(c.nume,c.deno);
 c.nume=c.nume/t;
 c.deno=c.deno/t;
 return c;
}
CFraction CFraction::operator /(CFraction &x)
{   
 CFraction c;
 int t;
 c.nume=nume*x.deno;
 c.deno=deno*x.nume;
    t=g(c.nume,c.deno);
 c.nume=c.nume/t;
 c.deno=c.deno/t;
 return c;
}

bool CFraction::operator >(CFraction &x)
{   
 //bool flag=true;
    CFraction c;
 int t=f(deno,x.deno);
 c.nume=nume*(t/deno)-(t/x.deno)*x.nume;
 if(c.nume>0)
 {
   return true;
 }
 else
 {
  //flag=false;
  return false;
 }

}
bool CFraction::operator <(CFraction &x)
{
 //bool flag=true;
 int t=f(deno,x.deno);
    CFraction c;
 c.nume=nume*(t/deno)-(t/x.deno)*x.nume;
 if(c.nume<0)
 {
  return true;
 }
 else
 {
  //flag=false;
  return false;
 }
}
bool CFraction::operator =(CFraction &x)
{   
 //bool flag=true;
 int t=f(deno,x.deno);
    CFraction c;
 c.nume=nume*(t/deno)-(t/x.deno)*x.nume;
 if(c.nume=0)
 {
  return true;
 }
 else
 {
  //flag=false;
  return false;
 }
}

bool CFraction::operator >=(CFraction &x)
{   
 //bool flag=false;
 int t=f(deno,x.deno);
    CFraction c;
 c.nume=nume*(t/deno)-(t/x.deno)*x.nume;
 if(c.nume<0)
 {
  return false;
 }
 else
 {
  //flag=true;
  return true;
 }
}
 bool CFraction::operator <=(CFraction &x)
{   
 //bool flag=false;
 int t=f(deno,x.deno);
 CFraction c;
 c.nume=nume*(t/deno)-(t/x.deno)*x.nume;
 if(c.nume>0)
 {
  return false;
 }
 else
 {
  //flag=true;
  return true;
 }
}
bool CFraction::operator !=(CFraction &x)//注意开头的形式
{
 //bool flag=false;
 int t=f(deno,x.deno);
    CFraction c;
 c.nume=nume*(t/deno)-(t/x.deno)*x.nume;
 if(c.nume==0)
 {
  return false;
 }
 else
 {
  //flag=true;
  return true;
 }
}
/*CFraction CFraction:: operator -()
{
 //*this=this*(-1);
 return(0- *this);
}*/
int CFraction::f(int x,int y)
{
 int t,p,r;
 if(x<y)
 {
  t=x;
  x=y;
  y=t;
 }
 p=x*y;
 while(y!=0)
 {
  r=x%y;
  x=y;
  y=r;
 }
 return p/x;
}
int CFraction:: g(int x,int y)
{
 int t,p,r;
 if(x<y)
 {
  t=x;
  x=y;
  y=t;
 }
 p=x*y;
 while(y!=0)
 {
  r=x%y;
  x=y;
  y=r;
 }
 return x;
}
void CFraction:: display()
{
 cout<<nume<<'/'<<deno;
}
void main()
{
 CFraction x1(3,12),x2(1,3);
 cout<<"x1=";
 x1.display();
 cout<<endl;
    cout<<"x2=";
 x2.display();
 cout<<endl;
 cout<<"x1+x2=:";
 (x1+x2).display();
 cout<<endl;
 cout<<"x1-x2=:";
 (x1-x2).display();
 cout<<endl;
 cout<<"x1*x2=:";
 (x1*x2).display();
 cout<<endl;
 cout<<"x1/x2=:";
 (x1/x2).display();
 cout<<endl;
 if(x1<x2) cout<<"x1<x2";
 cout<<endl;
 if(x1!=x2) cout<<"x1!=x2";
}

感悟：1.自己闷着脑袋做出来的很爽。

2.注意定义运算符函数头的形式，要死记住。

3.在定义求反时，电脑上说：二进制“-”: 没有找到接受“CFraction”类型的全局运算符(或没有可接受的转换)？为啥？？？？？？？？？？？？？？？？