shape.dart

class IShape{
  void draw(){}
}

class Rectangle implements IShape{
  void draw(){
    print("Inside Rectangle::draw() method.");  
  }
}

class Square implements IShape{
  void draw(){
    print("Inside Square::draw() method.");
  }
}

class Circle implements IShape{
  void draw(){
    print("Inside Circle::draw() method.");
  }
}