public class Complex {

	private final double real;
	private final double imag;
	
	public Complex(double real, double imag) {
		this.real = real;
		this.imag = imag;
	}
	
	public Complex add(Complex z) {
		double real = this.real + z.real;
		double imag = this.imag + z.imag;
		return new Complex(real, imag);
	}
	
	public Complex times(Complex z) {
		double real = this.real*z.real - this.imag*z.imag;
		double imag = this.real*z.imag + this.imag*z.real;
		return new Complex(real, imag);
	}
	
	public double abs() {
		return Math.sqrt(real*real+imag*imag);
	}
}