complex复数类

#include<iostream>
#include<cmath> 
using namespace std;
class complex{
    public:
        complex(double a,double b);
        complex(complex &n);
        void add(complex &f);
        void show();
        double mod();
    private:
        double real;
        double imaginary;
    };
complex::complex(double a,double b=0):real(a),imaginary(b){cout<<a<<" "<<b<<endl;
}
complex::complex(complex &n):real(n.real),imaginary(n.imaginary){
}

void complex::add(complex &f){
    real+=f.real;
    imaginary+=f.imaginary;
}
void complex::show(){
    cout<<real<<"+"<<imaginary<<"i"<<endl;
}
double complex::mod(){
    double z;
    z=sqrt(real*real+imaginary*imaginary);
    return z;
}

        
int main()
{complex c1(3,5);
 complex c2(4.5);
 complex c3(c1);
 c1.add(c2);
 c1.show();
 cout<<c1.mod()<<endl;
 return 0;
}

【程序结果】