ch8_8.cpp

大整数四则运算的例子和算法介绍

#include <iostream.h>

class complex {
private:
  double real;
  double image;
public:
  complex(double r = 0.0 , double i = 0.0 ){ real=r;  image=i; }
  friend complex operator +(const complex & x,const complex & y);
  friend complex operator -(const complex & x,const complex & y);
  complex operator -();
  void operator =(const complex& c2);
  void display() const;
};

complex operator +(const complex & x,const complex & y)
{
  double r = x.real+y.real;
  double i = x.image+y.image;
  return complex(r,i);
}

complex operator -(const complex & x,const complex & y)
{
  double r = x.real-y.real;
  double i = x.image-y.image;
  return complex(r,i);
}

complex complex::operator -()
{
  return complex(-real,-image);
}

void complex::operator =(const complex & c2)
{
  real = c2. real ;
  image = c2. image ;
}

void complex::display() const
{
  cout<<"("<<real<<"+"<<image<<"i)"<<endl;
}

void main()
{
  complex a(2,3);
  complex b(4,5);
  complex c=a+b;  //  c = operator + (a,b)
  complex d=a-b;  //  d = operator - (a,b)
  complex e=-a;   //  e = operator - (a)
  complex f=e;
  c.display();
  d.display();
  e.display();
  f.display();
}