#include <cmath>
#include <iostream>

using namespace std;

class Complex {
public:
    double real, imag;

    Complex(double r, double i) {
        real = r;
        imag = i;
    }

    Complex(double r) {
        real = r;
        imag = 0;
    }

    Complex operator + (const Complex& c) {
        return Complex (real + c.real, imag + c.imag);
    }

    Complex operator - (Complex& c) {
        return Complex (real - c.real, imag - c.imag);
    }

    Complex operator * (Complex& c) {
        return Complex (real * c.real - imag * c.imag, imag * c.real + real * c.imag);
    }

    Complex operator / (Complex& c) {
        return Complex ((real * c.real + imag * c.imag) / (c.real * c.real + c.imag * c.imag),
                        (imag * c.real - real * c.imag) / (c.real * c.real + c.imag * c.imag));
    }

    Complex operator + () {
        return Complex (real, imag);
    }

    Complex operator - () {
        return Complex (-real, -imag);
    }

    double Re() {
        return real;
    }

    double Im() {
        return imag;
    }

    bool operator == (Complex& c) {
        return (real == c.real && imag == c.imag);
    }

    bool operator != (Complex& c) {
        return (real != c.real || imag != c.imag);
    }
};

double abs(Complex& c) {
    return sqrt (c.real * c.real + c.imag * c.imag);
}