设计、定义并实现Complex类

#include<iostream>
#include<math.h>
using namespace std;
class Complex{
    public:
        Complex(double real0=0,double imag0=0);
        Complex(Complex &p);
        void add(Complex A);
        void show();
        double mod();
    private:
        double real;
        double imag;        
}; 
Complex::Complex(Complex &p)
{
    real=p.real;
    imag=p.imag;
}
Complex::Complex(double real0,double imag0)
{
    real=real0;
    imag=imag0;
}
void Complex::show()
{
    cout<<real<<"+"<<imag<<"i"<<endl;
}
void Complex::add(Complex A)
{
    real=real+A.real;
    imag=imag+A.imag;
}
double Complex::mod()
{
    double s=real*real+imag*imag;
    double m=sqrt(s);
    return m;
}
int main()
{
    Complex c1(3,5);
    Complex c2(4.5);
    Complex c3(c1);
    c1.add(c2);
    c1.show();
    cout<<c1.mod();
    return 0;
}