c++訓練營

// demo1.cpp :

定義控制台應用程式的入口點。

//通過此例程了解重載

#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

 double Div(double a,double b);

 int Add(int a,int

b)

  return a+b;

 int Sub(int a,int

  return a-b;

 int Mul(int a,int

  return a*b;

 int Div(int a,int

  if

(b!=0)

  {

   return

a/b;

  }

  return

0;

 CMath operator +(CMath&

mymath)

  CMath

result(0);

  result.m_a=m_a+mymath.m_a;

  return result;

 CMath

operator -(CMath& mymath)

  result.m_a=m_a-mymath.m_a;

operator *(CMath& mymath)

  result.m_a=m_a*mymath.m_a;

operator /(CMath& mymath)

(mymath.m_a==0)

   mymath.m_a=1;

  result.m_a=m_a/mymath.m_a;

operator

++()//前++

  this->m_a+=1;

*this;

 CMath operator

++(int)//後++,加上參數int,無意義

*t=this;

  ++(t->m_a);

*t;

--()//前--

  this->m_a-=1;

--(int)//後--，加上參數int,無意義

  --(this->m_a);

 CMath operator +=(CMath &

  m_a+=mymath.m_a;

  CMath operator -=(CMath &

  m_a-=mymath.m_a;

 bool operator ==(CMath

&mymath)

(m_a==mymath.m_a);

 friend ostream& operator

<<(ostream &os,CMath &t);//必須是友元

 friend

iostream& operator >>(iostream &is,CMath

&t);//必須是友元

operator ()(const CMath& t)

CMath(this->m_a=t.m_a);

 CMath& operator =(CMath

&t)

  this->m_a=t.m_a;

private:

 float m_a;

};

ostream&

operator <<(ostream &os,CMath

 os<<t.m_a<<endl;

 return os;

}

 is>>t.m_a;

 return

is;

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

a+b;

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

a-b;

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

a*b;

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

 if

(b==0)

  b=1;

int _tmain(int argc, _TCHAR*

argv[])

mymath(4);

 cout<<mymath.Add(1.1,2.1)<<endl;//調用參數為double類型的Add函數

 cout<<mymath.Add(1,2)<<endl;//調用參數為int類型的Add函數

 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;

mymath1(20);

 mymath=mymath1;

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

(mymath==mymath1)

  cout<<"mymath==mymath1"<<endl;

 mymath1+=mymath;

 cout<<"mymath1:"<<mymath1<<endl;

 mymath1-=mymath;

 mymath1(mymath);

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