[nerv_]

class Animal {
  constructor(name) {
  	this.name = name;
  }
}

class Dog extends Animal {
  constructor(name) {
  	super(name);
  }
  bark(dogName) {
  	return this.name + dogName;
  }
}


let dog = new Dog('Balto');
console.log(dog.name);
console.log(dog.bark('test'));