DATA STRUCTURE INTERVIEW QUESTION & ANSWERS
11. 
What is a complete binary tree? 

A complete binary tree is a binary tree in which every level of the tree is completely filled except for the last (bottom) level. In the last level, the leaves are filled from die left to right. 
12. 
What are the types of binary tree representation? 

There are two ways of representing the binary tree :  Sequential representation and

Linked representation

13. 
What is state space tree? 

A state space tree is a rooted free whose nodes represent partially constructed solutions to given problem. In backtracking and branch and bound technique, building state space tree for finding the solution – is a basic principle. In backtracking technique the state space tree is constructed in depth first search fashion. 
14. 
What is B–tree? 

B–tree is a specialized multiway tree used to store the records in a disk. There are number of subtrees to each node. So that the height of the tree is relatively small. So
that only small number of nodes must be read from disk to retrieve an item. The goal of B–trees is to get fast access of the data.

15. 
What is an AVL tree? 

An AVL tree (named after its inventors Adelson–Velskii and
Landis} is a height balanced tree. For every node in the tree, the heights of left and right sub trees differ by at most 1 level, so it is a balanced tree. 