类型转换构造函数

目的：

特点：

#include<stdio.h>
#include<stdlib.h>
#include<iostream>
using namespace std;
class complex{
private:
double real,imag;
public:
complex(int i)//类型转换构造函数
{
cout<<"Intconstructor is called"<<endl;
real=i;
imag=0;
}
complex()
{
cout<<"no parameter constructor is called"<<endl;
}
complex(double x,double y)
{
real=x;
imag=y;
cout<<"constructor is called"<<endl;
}
complex(const complex&c)
{
real=c.real;
imag=c.imag;
cout<<"copy constuctor is called."<<endl;
}
void get_complex()
{
cout<<real<<"+"<<imag<<"i"<<endl;
}
};
complex fun()
{
complex a(1,2);
return a;
}
int main()
{
complex c1(7,8);
complex c2=12;//初始化语句,直接调用complex(int)初始化c2
c1=9;//赋值语句，9被自动转化为一个临时的complex对象，然后将临时对象的值赋值给c1
c1.get_complex();
return 0;
}

constructor is called
Intconstructor is called
Intconstructor is called
9+0i