OOP 复数类重载*运算符

1.为该复数类重载*运算符，以友元的形式重载；为该复数类重载赋值运算，可接收的字符 串如：3+5i , -3+2i , 7-8i。

代码 :

#include <iostream>
#include <stdlib.h>
#include <stdio.h>
#include <string>
using namespace std;

class Complex
{
	double real;
	double image;

public:
	Complex(double r = 0, double i = 0);
	Complex(const Complex& other);
	void print();
	Complex operator + (const Complex& other);
	Complex operator - (const Complex& other); //减法， 二元
	Complex operator - ();  //求负，一元
	Complex operator = (const Complex& other); //赋值， 二元

	friend Complex operator* (const Complex& a, const Complex& b);//重载*
	Complex operator = (string s); //赋值,接收的字符串


};
Complex::Complex(double r, double i)
{
	real = r;
	image = i;
}
Complex::Complex(const Complex& other)
{  //此拷贝构造函数与缺省拷贝函数相同，可以省略。
	real = other.real;
	image = other.image;
}
void Complex::print()
{
	cout << real;
	if (image > 0)
		cout << "+" << image << "i";
	else if (image < 0)
		cout << image << "i";
	cout << "\n";
}
Complex Complex:: operator + (const Complex& other)
{
	Complex temp;
	temp.real = real + other.real;   //相当于temp.real=this->real+other.real;
	temp.image = image + other.image;
	return temp;
}
Complex Complex:: operator - (const Complex& other)
{
	Complex temp;
	temp.real = real - other.real;
	temp.image = image - other.image;
	return temp;
}
Complex Complex:: operator - ()
{
	Complex temp;
	temp.real = -real;
	temp.image = -image;
	return temp;
}
Complex Complex:: operator = (const Complex& other)
{  //此赋值运算符的重载与缺省赋值运算相同，可以省略。
	real = other.real;
	image = other.image;
	return *this;
}

Complex operator*(const Complex& a, const Complex& b)//重载*
{
	Complex tmp;
	tmp.real = a.real * b.real - a.image * b.image;
	tmp.image = a.real * b.image + a.image * b.real;
	return tmp;
}
Complex Complex::operator = (string s) //赋值,接收的字符串
{
	int i{}, n = -1;
	string temp;
	if (s.find('i') == s.npos)//如果没有虚部
	{
		image = 0;
		real = stoi(s);
	}
	else
	{
		temp.push_back(s[0]);
		if (s.find('+') != s.npos)
			n = s.find('+');
		else if (s.find('-') != s.npos)
			n = s.find('-');
		else
		{
			real = 0;
			n = -1;
		}
		if (n != -1)
		{
			for (i = 1; i < n; i++)
			{
				temp.push_back(s[i]);
			}
			real = stoi(temp);
		}
		temp.clear();
		for (; i < s.rfind('i'); i++)
		{
			if (s[i] != '+' && s[i] != '-')
				temp.push_back(s[i]);
			else if (s[i] == '-')
				temp.push_back(s[i]);
			else if (s[i] == '+')
				continue;
		}
		image = stoi(temp);
	}
	return *this;
}
int main()
{
	int m;
	cout << "请选择输入方式；(1 字符输入 | 2 输入实部和虚部)" << endl;
	cin >> m;
	if (m == 1)
	{
		cout << "请输出实部和虚部 ：" << endl;
		double c1_real, c1_image, c2_real, c2_image;
		cin >> c1_real >> c1_image >> c2_real >> c2_image;
		Complex c1(c1_real, c1_image);
		Complex c2(c2_real, c2_image);
		Complex c3;
		cout << "c1：";
		c1.print();
		cout << "c2：";
		c2.print();
		c3 = c1 * c2;
		cout << "c3 = c1*c2 ：";
		c3.print();
	}
	else if (m == 2)
	{
		Complex c1, c2, c3;
		string s1, s2;
		cout << "请输入字符串：" << endl;
		cin >> s1;
		getchar();
		cin >> s2;
		c1 = s1;
		cout << "c1 : ";
		c1.print();
		c2 = s2;
		cout << "c2 : ";
		c2.print();
		c3 = c1 * c2;
		cout << "c3 = c1*c2 : ";
		c3.print();
	}
	else
		cout << "Error!" << endl;
	system("PAUSE");
	return 0;
}

运行结果：