SDE - Intern

You are given a Binary Tree of 'n' nodes.

The Top view of the binary tree is the set of nodes visible when we see the tree from the top.

Find the top view of the given binary tree, from left to right.

Example :

Input: Let the binary tree be:

Output: [10, 4, 2, 1, 3, 6]

Explanation: Consider the vertical lines in the figure. The top view contains the topmost node from each vertical line.

You are given the root node of a binary tree.

Return 'true' if it is a height balanced binary tree.

Note:

Height of a tree is the maximum number of nodes in a path from the node to the leaf node.

An empty tree is a height-balanced tree. A non-empty binary tree is a height-balanced binary tree if
1. The left subtree of a binary tree is already the height-balanced tree.
2. The right subtree of a binary tree is also the height-balanced tree.
3. The difference between heights of left subtree and right subtree must not more than ‘1’.

Example:

Input: Consider the binary tree given below:

Output: 'true'

Explanation:
Consider subtree at Node ( 7 ) 
Left subtree height is ‘0’ and right subtree height is ‘0’, the absolute height difference is ‘0-0 = 0’ and ‘0’ is not more than ‘1’ so subtree at Node ( 7 ) is a height-balanced binary tree. 
Same for subtrees at Nodes ( 5, 6 ). 

Consider subtree at Node ( 4 ) 
Left subtree height is ‘1’ and right subtree height is ‘0’, the absolute height difference is ‘1-0 = 1’ and ‘1’ is not more than ‘1’ so subtree at Node ( 4 ) is a height-balanced binary tree.
Same for subtree at Node ( 3)

Consider subtree at Node ( 2 ) 
Left subtree height is ‘2’ and right subtree height is ‘1’, the absolute height difference is ‘2-1 = 1’ and ‘1’ is not more than ‘1’ so subtree at Node ( 2 ) is a height-balanced binary tree.

Consider subtree at Node ( 1 ) 
Left subtree height is ‘3’ and right subtree height is ‘2’, the absolute height difference is ‘3-2 = 1’ and ‘1’ is not more than ‘1’ so subtree at Node ( 1 ) is a height-balanced binary tree.

Because the root node ( 1 ) is a height-balanced binary tree, so the complete tree is height-balanced.

You have been given a singly linked list in which nodes are present in increasing order. Your task is to construct a Balanced Binary Search Tree with the same data elements as the given Linked List.

A Balanced BST is defined as a BST in which the height of two subtrees of every node differs no more than 1.