ch18_4.cpp

上面的程序是关于钱能的C++课后习题答案

//**********************
//**    ch18_4.cpp    **
//**********************

#include <iostream.h>

class Increase{
public:
  Increase(int x):value(x){}
  Increase & operator++();      //前增量
  Increase operator++(int);     //后增量
  void display(){ cout <<"the value is " <<value <<endl; }
private:
  int value;
};

Increase & Increase::operator++()
{
  value++;                      //先增量
  return *this;                 //再返回原对象
}

Increase Increase::operator++(int)
{
  Increase temp(*this);         //临时对象存放原有对象值
  value++;                      //原有对象增量修改
  return temp;                  //返回原有对象值
}

void main()
{
  Increase n(20);
  n.display();
  (n++).display();              //显示临时对象值
  n.display();                  //显示原有对象
  ++n;
  n.display();
  ++(++n);
  n.display();

  (n++)++;                      //第二次增量操作对临时对象进行
  n.display();
}