//জাভা (Java)
interface Animal {
  void makeSound();
}
interface Movable {
  void move();
}
abstract class Bird implements Animal, Movable {
  // implement
  public void makeSound() {
    System.out.println(“Tweet tweet”);
  }
  // keeping as abstract
  public abstract void move();
}
class Sparrow extends Bird {
  // Implement the move method
  public void move() {
    System.out.println(“Sparrow Fly in the sky”);
  }
}

//জাভা (Java)
interface Animal {
  void makeSound(); // Abstract method declaration
}
// implements Animal
abstract class Bird implements Animal {
  public void makeSound() { // Concrete method implementation
    System.out.println(“Tweet tweet”);
  }
  public abstract void fly(); // Abstract method declaration
}
// Extends the abstract class + Override
class Sparrow extends Bird {
  public void fly() { // Concrete method implementation
    System.out.println(“Sparrow Fly in the sky”);
  }
  // Override the makeSound method from the Bird abstract class
  @Override
  public void makeSound() { // Concrete method implementation
    System.out.println(“Sparrow Chirp chirp”);
  }
}

//জাভা (Java)
interface Animal {
  void makeSound(); // Abstract method declaration
}
// implements Animal
abstract class Bird implements Animal {
  public void makeSound() { // Concrete method implementation
    System.out.println(“Tweet tweet”);
  }
  public abstract void fly(); // Abstract method declaration
}
// Extends the abstract class + Override
class Sparrow extends Bird {
  public void fly() { // Concrete method implementation
    System.out.println(“Sparrow Fly in the sky”);
  }
  // Override the makeSound method from the Bird abstract class
  @Override
  public void makeSound() { // Concrete method implementation
    System.out.println(“Sparrow Chirp chirp”);
  }
}

//জাভা (Java)
abstract class Shape {
  // Define a field
  protected String color;
  // Define a constructor
  public Shape(String color) {
    this.color = color;
  }
  // abstract method, partial abstraction
  public abstract double getArea();
  // Define a concrete method
  public void printColor() {
    System.out.println(“The color is ” + color);
  }
}

//জাভা (Java)
using System;
abstract class Shape {
    public abstract double getArea();
    public abstract double getPerimeter();
}