设计、定义并实现Complex类

#include <iostream> 
#include <cmath>
using namespace std;
class Complex{
    public:
        Complex(double real0,double imaginary0);
        Complex(double real0);
        Complex(Complex &a);
        void add(Complex b);
        void show();
        double mod();
    private:
        double real;
        double imaginary; 
        
};
Complex::Complex(double real0,double imaginary0):real(real0),imaginary(imaginary0){
}
Complex::Complex(double real0):real(real0){
}
Complex::Complex(Complex &a):real(a.real),imaginary(a.imaginary){
}
void Complex::add(Complex b){
    real=real+b.real;
    imaginary=imaginary+b.imaginary;
}
void Complex::show(){
    cout<<real<<"+"<<imaginary<<"i"<<endl;
}
double Complex::mod(){
    double m;
    m=sqrt(real*real+imaginary*imaginary);
    return m;
}
int main()
{ Complex c1(3,5);
  Complex c2(4.5);
  Complex c3(c1);
  c1.add(c2);
  c1.show();
  cout<<c1.mod()<<endl;
  return 0;
}