c++训练营--重载

// demo1.cpp : 定义控制台应用程序的入口点。

//通过此例程了解重载

#include "stdafx.h"

#include <iostream>

using namespace std;

 

class CMath

{

public:

 CMath(float a):m_a(a)

 {

 }

 ~CMath()

 {

 }

 double Add(double a,double b);

 double Sub(double a,double b);

 double Mul(double a,double b);

 double Div(double a,double b);

 int Add(int a,int b)

 {

  return a+b;

 }

 int Sub(int a,int b)

 {

  return a-b;

 }

 int Mul(int a,int b)

 {

  return a*b;

 }

 int Div(int a,int b)

 {

  if (b!=0)

  {

   return a/b;

  }

  return 0;

 }

public:

 CMath operator +(CMath& mymath)

 {

  CMath result(0);

  result.m_a=m_a+mymath.m_a;

  return result;

 }

 CMath operator -(CMath& mymath)

 {

  CMath result(0);

  result.m_a=m_a-mymath.m_a;

  return result;

 }

 CMath operator *(CMath& mymath)

 {

  CMath result(0);

  result.m_a=m_a*mymath.m_a;

  return result;

 }

 CMath operator /(CMath& mymath)

 {

  if (mymath.m_a==0)

  {

   mymath.m_a=1;

  }

  CMath result(0);

  result.m_a=m_a/mymath.m_a;

  return result;

 }

 CMath operator ++()//前++

 {

  this->m_a+=1;

  return *this;

 }

 CMath operator ++(int)//后++,加上參数int,无意义

 {

  CMath *t=this;

  ++(t->m_a);

  return *t;

 }

 CMath operator --()//前--

 {

  this->m_a-=1;

  return *this;

 }

 CMath operator --(int)//后--，加上參数int,无意义

 {

  CMath *t=this;

  --(this->m_a);

  return *t;

 }

 CMath operator +=(CMath & mymath)

 {

  m_a+=mymath.m_a;

  return *this;

 }

  CMath operator -=(CMath & mymath)

 {

  m_a-=mymath.m_a;

  return *this;

 }

 bool operator ==(CMath &mymath)

 {

  return (m_a==mymath.m_a);

 }

 friend ostream& operator <<(ostream &os,CMath &t);//必须是友元

 

 

 friend iostream& operator >>(iostream &is,CMath &t);//必须是友元

 

 

 CMath operator ()(const CMath& t)

 {

  return CMath(this->m_a=t.m_a);

 }

 CMath& operator =(CMath &t)

 {

  this->m_a=t.m_a;

  return *this;

 }

private:

 float m_a;

};

 

ostream& operator <<(ostream &os,CMath &t)

{

 os<<t.m_a<<endl;

 return os;

}

iostream& operator >>(iostream &is,CMath &t)

{

 is>>t.m_a;

 return is;

}

 

double CMath::Add(double a,double b)

{

 return a+b;

}

 

double CMath::Sub(double a,double b)

{

 return a-b;

}

 

double CMath::Mul(double a,double b)

{

 return a*b;

}

 

double CMath::Div(double a,double b)

{

 if (b==0)

 {

  b=1;

 }

 return a/b;

}

int _tmain(int argc, _TCHAR* argv[])

{

 CMath mymath(4);

 cout<<mymath.Add(1.1,2.1)<<endl;//调用參数为double类型的Add函数

 cout<<mymath.Add(1,2)<<endl;//调用參数为int类型的Add函数

 cout<<mymath.Sub(1,2)<<endl;//

 cout<<mymath.Mul(1,2)<<endl;

 cout<<mymath.Div(1.3,2.3)<<endl;

 cout<<endl<<endl;

 cout<<"mymath:"<<mymath<<endl;

 mymath++;

 cout<<"mymath++:"<<mymath<<endl;

 mymath--;

 cout<<"mymath--:"<<mymath<<endl;

 cout<<"mymath+mymath:"<<mymath+mymath<<endl;

 cout<<"mymath*mymath:"<<mymath*mymath<<endl;

 cout<<"mymath/mymath:"<<mymath/mymath<<endl;

 CMath mymath1(20);

 mymath=mymath1;

 cout<<"mymath=mymath1:"<<mymath<<endl;

 if (mymath==mymath1)

 {

  cout<<"mymath==mymath1"<<endl;

 }

 mymath1+=mymath;

 cout<<"mymath1:"<<mymath1<<endl;

 mymath1-=mymath;

 cout<<"mymath1:"<<mymath1<<endl;

 mymath--;

 mymath1(mymath);

 cout<<"mymath1(mymath):"<<mymath1<<endl;

 

 return 0;

}