public class Point {
private int x;
private int y;
public Point(int x, int y) {
this.x = x;
this.y = y;
}
}
-------------------------------------------------
public class Circle extends Point{
public Circle(int x, int y) {
super(x, y);
}
private int r;
public Circle(int x, int y, int r) {
super(x, y);
this.r = r;
}
double area(){
double C=2*Math.PI*r;
return C;
}
double vol(){
double S=Math.PI*r*r;
return S;
}
}
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public class test {
public static void main(String[] args){
Point p1=new Point(3,4 );
Point p2=new Point(5,6 );
Circle c=new Circle(0,0 ,3 );
System.out.println(c.area());
System.out.println(c.vol());
}
}