import java.lang.*;

public class XYZVector extends Object implements Cloneable
{
	public double x, y, z;
	private double magnitude;
	
	public XYZVector(double xx, double yy, double zz)
	{
		x = xx; y = yy; z = zz;
		magnitude = Math.sqrt(x*x + y*y + z*z);
	}

	public XYZVector(double x0, double y0, double z0,
					 double x1, double y1, double z1)
	{
		x = x1-x0; y = y1-y0; z = z1-z0;
		magnitude = Math.sqrt(x*x + y*y + z*z);
	}
	
	public synchronized Object clone()
	{
		XYZVector b = new XYZVector(x, y, z);
		return b;
	}
	
	public static double dotProduct(XYZVector a, XYZVector b)
	{
		return (a.x * b.x + a.y * b.y + a.z * b.z);
	}
	
	public static XYZVector normalize(XYZVector b)
	{
		XYZVector a = (XYZVector) b.clone();
		if (a.magnitude != 1.0)
		{
			a.x /= a.magnitude;
			a.y /= a.magnitude;
			a.z /= a.magnitude;
			a.magnitude = 1.0;	
		}
		return a;
	}
	
	public void normalize()
	{
		if (magnitude != 1.0)
		{
			x /= magnitude;
			y /= magnitude;
			z /= magnitude;
			magnitude = 1.0;	
		}
		
	}
	
	public static XYZVector plus(XYZVector a, XYZVector b)
	{
		return new XYZVector(a.x + b.x, a.y + b.y, a.z + b.z);
	}
	
	public static XYZVector reverse(XYZVector a)
	{
		return new XYZVector(-a.x, -a.y, -a.z);
	}
	
	public static XYZVector minus(XYZVector a, XYZVector b)
	{
		return plus(a, reverse(b));
	}
	
	public double getMagnitude()
	{
		return magnitude;
	}
}