// 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++,加上参数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--，加上参数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;//调用参数为double类型的Add函数
 cout<<mymath.Add(1,2)<<endl;//调用参数为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;
}