课堂小练习: 设计、定义并实现Complex类

#include <iostream> 
#include <cmath>
using namespace std;
class Complex{
public:
    Complex(double a=0,double b=0);
    Complex(Complex &c);        
    void add(Complex p);
    void show();
    double mod();    
private:
     double x,y;        
};
Complex::Complex(double a,double b){
    x=a;
    y=b;
}
Complex::Complex(Complex &c){
    x=c.x;
    y=c.y;
}
void Complex::add(Complex c){
    x=c.x+x;
    y=c.y+y;
}
void Complex::show(){
    cout<<x<<"+"<<y<<"i"<<endl;
}
double Complex::mod(){
    return sqrt(pow(x,2)+pow(y,2));
}
int main(){
    Complex c1(3,5);
    Complex c2(4.5);
    Complex c3(c1);
    c1.add(c2);
    c1.show();
    cout<<c1.mod();
    return 0;
}