写一个复数类Complex，(复数形如3.2+5.6i,2.9-1.3i,其中i*i=-1)。要求支持＋－＊／，++、--，到bool类型和string类型的转换，支持>>、<<运算符。

// ConsoleApplication1.cpp : 定义控制台应用程序的入口点。//#include "stdafx.h"#include <iostream>using namespace std;class Complex{float a;float b;public:Complex():a(),b(){}Complex(const float& a, const float& b):a(a),b(b){}Complex operator+(const Complex& com2){return Complex((a+com2.a),(b+com2.b));}Complex operator-(const Complex& com2){return Complex((a-com2.a),(b-com2.b));}Complex operator*(const Complex& com2){return Complex((a*com2.a),(b*com2.b));}Complex operator/(const Complex& com2){return Complex((a/com2.a),(b/com2.b));}/*成员函数前置--:*/Complex& operator--(){--a;--b;return *this;}/*友元函数前置--:*///friend Complex& operator--(Complex& com)//{//--com.a;//--com.b;//return com;//}/*成员函数后置--:*//*Complex operator--(int){Complex temp(*this);a--;b--;return temp;}*//*友元函数后置--:*/friend Complex operator--(Complex& com,int)//(Complex& com,int)中不加& 就不能改变自己的值{Complex temp(com);com.a--;com.b--;return temp;}Complex& operator=(const Complex& b)//必须是成员函数,与=相关的都必须是成员函数,还有[ ]和(){this->a=b.a;this->b=b.b;return *this;}friend ostream& operator<<(ostream&o,const Complex& com)//必须是友元函数{return o << com.a << " + " << com.b << "i";}friend istream& operator>>(istream& in,Complex& com)//必须是友元函数{return in >> com.a >> com.b ;//return in >> com.a >> " + " >> com.b >>"i"; 错误 没有这些符号的定义}//void show()//{//char * str;//int dec, sign, ndigits = 3; //str = _fcvt_s(a, ndigits, &dec, &sign);//printf("Original number; %f\n" , a) ; //printf ("Converted string; %s\n",str);    //printf ("Decimal place: %d\n" , dec) ; //printf ("Sign: %d\n" , sign) ;           ////str = fcvt(b, ndigits, &dec, &sign);//}};int _tmain(int argc, _TCHAR* argv[]){Complex a(1,5);Complex b(5,6);a=a+b; cout << a << endl;cout << --a << endl;cout << a-- << endl;cout << a << endl;Complex c;cout << "a:" << a << endl;cout << "c:" << c << endl;c=a--;cout << "c:" << c << endl;c=a;cout << "c:" << c << endl;cin >> c ;cout << "c:" << c << endl;c.show();system("pause");return 0;}