import java.awt.*;
import java.util.*;

public class Circle {
	// class constants
	static public final int   DEFAULT_RADIUS = 1;
	static public final Point DEFAULT_CENTER = new Point(0, 0);
	
	//instance variables
	private int radius;
	private Point center;
	
	// constructors
	
	// default constructor
	public Circle() {
		this.setRadius(DEFAULT_RADIUS);
		this.setCenter(DEFAULT_CENTER);
	}
	
	// fully specified
	public Circle(int r, Point p) {
		this.setRadius(r);
		this.setCenter(p);
	}
	
	// radius get and set attribute methods
	
	public int getRadius() {
		return this.radius;
	}
	
	public void setRadius(int r) {
		if ( r > 0 ) {
			this.radius = r;
		}
		else {
			throw new NumberFormatException("Bad radius: " + r);
		}
	}
	
	// center get and set attribute methods
	
	public Point getCenter() {
		return this.center;
	}
	
	public void setCenter(Point p) {
		if ( p != null ) {
			this.center = p;
		}
		else {
			throw new NullPointerException("Bad center");
		}
	}
	
	// other methods
	
	// produce string representation
	public String toString() {
		String result = "Circle( radius: "
							+ this.getRadius() + ", center: ("
							+ this.getCenter().x + ", "
							+ this.getCenter().y + ") )";
		return result;
	}
	
	// compute distance from center to a specified point
	public double getDistance(Point there) {
		Point here = this.getCenter();
		
		int x1 = here.x;
		int y1 = here.y;

		int x2 = there.x;
		int y2 = there.y;
		
		int deltax = x1 - x2;
		int deltay = y1 - y2;
		
		double distance = Math.sqrt( deltax*deltax + deltay*deltay);
		
		return distance;
	}
	
	// compute distance from center to the center of a specified
	public double getDistance(Circle c) {
		Point p = c.getCenter();
		
		return this.getDistance(p);
	}

	// test whether this circle has same representation as there
	public boolean equals(Circle there) {
		int   r1 = this.getRadius();
		Point p1 = this.getCenter();
		
		int   r2 = there.getRadius();
		Point p2 = there.getCenter();
		
		return ( r1 == r2 ) && p1.equals(p2);
		
	}
	
	// duplicate
	public Object clone() {
		int   r = this.getRadius();
		Point p = this.getCenter();
		
		return new Circle(r, p);
	}

	// test whether this circle and there refer to the same object
	public boolean same(Circle there) {
		return this == there;
	}
	
	// test whether this circle has a common representation as there
	public boolean equals(Object there) {
		if ( there instanceof Circle) {
			return this.equals( (Circle) there );
		}
		else {
			return false;
		}
	}
	
	// demo
	public static void main(String[] args) {
		int   r = 5;
		Point p = new Point(50, 50);
		
		Circle c1 = new Circle();
		Circle c2 = new Circle(r, p);
		Circle c3 = (Circle) c2.clone();
		
		try {
			c1.setRadius(-10);
		} 
		catch (Exception e) {
			c1.setRadius(1000);
		}

		System.out.println();
		
		System.out.println("c1 = " + c1);
		System.out.println("c2 = " + c2);
		System.out.println("c3 = " + c3);
		
		System.out.println();

		System.out.println("c1 == c2: " + ( c1 == c2 ) );
		System.out.println("c1 == c3: " + ( c1 == c3 ) );
		System.out.println("c2 == c3: " + ( c2 == c3 ) );
		
		System.out.println();

		System.out.println("c1.equals(c2): " + c1.equals(c2) );
		System.out.println("c1.equals(c3): " + c1.equals(c3) );
		System.out.println("c2.equals(c3): " + c2.equals(c3) );
		
		System.out.println();
	}
}