import java.util.HashMap;
import java.util.Map;

abstract class Animal {
      Map<String, Object> m1 = new HashMap<String,Object>();
      {
    	m1.put("Cow", new Cow());
      }

      abstract int age();
}

class Cow extends Animal {
	@Override
	int age() {
		// TODO Auto-generated method stub
		return 0;
	}
}