package Fourup;
public interface Shape {
public abstract double area(double a) ;
}
package Fourup;
public class Square implements Shape{
public double area(double a) {
double s;
s=a*a;
return s;
}
}
package Fourup;
public class Circle implements Shape {
public double area(double a) {
double s;
s=(Math.PI)*a*a;
return s;
}
}
package Fourup;
public class Tests {
public static void man(String []args) {
Square s = new Square();
Circle c = new Circle();
System.out.println(s.area(2.0));
System.out.println(c.area(3.0));
}
}
