In 'a class'(House class) parametrize constructor will call First.
in that you are using this()."this" key
word represents current class objects,constructors,instance variables.so automatically 'a class'(house class)class default constructor called.But first Base class(building) constructor called,then derived class default constructor.after that remaining code in parametrized constructor of 'a class' will execute.
note:super class default constructor is always available to subclass but parametrized one not available,to make it available you need use super keyword.so default constructor will always called until you use super keyword.
i think you got the concept
