完善的复数类

完善的复数类

1、复数类应该具有的操作

• 运算：+，-，*，/
• 比较：==，！=
• 赋值：=
• 求模：modulus

2、利用操作符重载

• 统一复数与实数的运算方式
• 统一复数与实数的比较方式

Complex operator + (const Complex& c);
Complex operator - (const Complex& c);
Complex operator * (const Complex& c);
Complex operator / (const Complex& c);

bool operator == (const Complex& c);
bool operator != (const Complex& c);

Complex& operator = (const Complex& c);

3、编程实验

//Complex.h

#ifndef _COMPLEX_H_
#define _COMPLEX_H_

class Complex
{
	double a;
	double b;
public:
	Complex(double a = 0, double b = 0);
	double getA();
	double getB();
	double getModulus();
	
	Complex operator + (const Complex& c);
	Complex operator - (const Complex& c);
	Complex operator * (const Complex& c);
	Complex operator / (const Complex& c);

	bool operator == (const Complex& c);
	bool operator != (const Complex& c);

	Complex& operator = (const Complex& c);
};

#endif

//Complex.cpp

#include "Complex.h"
#include <math.h>

Complex::Complex(double a, double b)
{
	this->a = a;
	this->b = b;
}

double Complex::getA()
{
	return a;
}

double Complex::getB()
{
	return b;
}

double Complex::getModulus()
{
	return sqrt(a * a + b * b);
}

Complex Complex::operator + (const Complex& c)
{
	double na = a + c.a;
	double nb = b + c.b;
	Complex ret(na, nb);

	return ret;
}

Complex Complex::operator - (const Complex& c)
{
	double na = a - c.a;
	double nb = b - c.b;
	Complex ret(na, nb);

	return ret;
}

Complex Complex::operator * (const Complex& c)
{
	double na = a * c.a - b * c.b;
	double nb = b * c.a + a * c.b;
	Complex ret(na, nb);

	return ret;
}

Complex Complex::operator / (const Complex& c)
{
	double na = (a * c.a + b * c.b) / (c.a * c.a + c.b * c.b);
	double nb = (b * c.a - a * c.b) / (c.a * c.a + c.b * c.b);
	Complex ret(na, nb);

	return ret;
}


bool Complex::operator == (const Complex& c)
{
	return (a == c.a) && (b == c.b);
}

bool Complex::operator != (const Complex& c)
{
	return !(*this == c);
}

Complex& Complex::operator = (const Complex& c)
{
	if(this != &c)
	{
		a = c.a;
		b = c.b;
	}
	return *this;
}

//test.cpp

#include <stdio.h>
#include <string.h>
#include "Complex.h"

int main()
{
	Complex c1(1,2);
	Complex c2(3,6);

	Complex c3 = c2 - c1;
	Complex c4 = c1 * c3;
	Complex c5 = c2 / c1;
	
	printf("c1.a = %f, c1.b = %f\n",c1.getA(),c1.getB());
	printf("c2.a = %f, c2.b = %f\n",c2.getA(),c2.getB());
	printf("c3.a = %f, c3.b = %f\n",c3.getA(),c3.getB());
	printf("c4.a = %f, c4.b = %f\n",c4.getA(),c4.getB());
	printf("c5.a = %f, c5.b = %f\n",c5.getA(),c5.getB());

	Complex c6(2,4);
	printf("c3 == c6:%d \n",c3 == c6);

	(c3 = c2) = c1;
	printf("c1.a = %f, c1.b = %f\n",c1.getA(),c1.getB());
	printf("c2.a = %f, c2.b = %f\n",c2.getA(),c2.getB());
	printf("c3.a = %f, c3.b = %f\n",c3.getA(),c3.getB());

	return 0;
}


//编译运行
$ ./a.out 
c1.a = 1.000000, c1.b = 2.000000
c2.a = 3.000000, c2.b = 6.000000
c3.a = 2.000000, c3.b = 4.000000
c4.a = -6.000000, c4.b = 8.000000
c5.a = 3.000000, c5.b = 0.000000
c3 == c6:1 
c1.a = 1.000000, c1.b = 2.000000
c2.a = 3.000000, c2.b = 6.000000
c3.a = 1.000000, c3.b = 2.000000

4、注意事项

1. C++规定赋值操作符（=）只能重载为成员函数
2. 操作符重载不能改变原操作符的优先级
3. 操作符重载不能改变操作数的个数
4. 操作符重载不能改变操作符的原有语义