运算符重载

1.C++提供了单目运算符和二元运算符的重载，这样可方便同类成员函数对不同数据类型的操作，返回值操作类型也可能不同，

//add.hpp
#ifndef _HHADD
#define _HHADD
class add
{
public:
  int temp;
  //int b;
  add()
  {
  temp=0;
  }
};
#endif
//addHPP.hpp
#include "add.hpp"
add operator+(add inputfi, int b)
{
return add(inputfi.temp+b);
};
//main.cpp
#include "add.hpp"
#include "addFUN.hpp"
#include <iostream>
using namespace std;
int main()
{
add output1(3),sum;
//sum.b=output1.operator+(output2);
sum=output1+8;
cout<<"the sum of the results"<<sum.temp<<endl;
return 0;

}

class A
{
public:
 int a;
 int b;
 int c;
 A(): a(0), b(0),c(0)
{}//default constructor
 A(int d, int e, int f):a(d),b(e),c(f)
{}//chongzai constructor
};
A operator+(const A &ori)
{
a=a+ori.a;
b=b+ori.b;
c=c+ori.c;
return *this;
}
};
int main()
{
A, output1,output2(10,20,30);
output1+=output2;
cout<<output1.a<<output1.b<<output1.c<<endl;
return 0;
}