Backend Developer

You are given a binary tree having 'n' nodes.

The boundary nodes of a binary tree include the nodes from the left and right boundaries and the leaf nodes, each node considered once.

Figure out the boundary nodes of this binary tree in an Anti-Clockwise direction starting from the root node.

Example :

Input: Consider the binary tree A as shown in the figure:

Output: [10, 5, 3, 7, 18, 25, 20]

Explanation: As shown in the figure

The nodes on the left boundary are [10, 5, 3]

The nodes on the right boundary are [10, 20, 25]

The leaf nodes are [3, 7, 18, 25].

Please note that nodes 3 and 25 appear in two places but are considered once.

You are given an array/list ARR of integers and a positive integer ‘K’. Your task is to find two non-overlapping subarrays (contiguous) each of length ‘K’ such that the total sum of these subarrays is maximum.

For Example:

If you are given ARR = [2, 5, 1, 2, 7, 3, 0] and K = 2, the output is 17. 

We can choose non-overlapping subarrays [2, 5] and [7, 3] to get a total sum of 17 (i.e. 2 + 5 + 7 + 3) which is the maximum possible sum.

You can assume that the array will always contain at least two non-overlapping subarrays with size ‘K’. So, the answer will always exist.

You are given an N x N chessboard and a knight. On a chessboard, the knight can supposedly move in 8 different positions from its original position i.e. if the knight is originally at (i,j) then it can move to (i + 2, j + 1), (i + 2, j - 1), (i - 2, j + 1), (i - 2, j - 1), (i + 1, j + 2), (i + 1, j - 2), (i - 1, j + 2), (i - 1, j - 2).

The rows and columns are 0 indexed, so the top-left square is (0, 0), and the bottom-right square is (N - 1, N - 1).

(X is the Knight’s current position, O is the position Knight can visit in 1 move)

You have to make K such moves from the initial position of the knight and tell the probability of the knight being within the boundaries of the chessboard i.e you have to consider all possibilities of K moves and determine the probability that after these moves the knight will remain within the chess grid.

Note:

Print output up to 6 decimal places.

Given a Binary Tree, convert this binary tree to a Doubly Linked List.

A Binary Tree (BT) is a data structure in which each node has at most two children.

A Doubly Linked List contains a previous pointer, along with the next pointer and data.

The order of nodes in Doubly Linked List must be the same as Inorder of the given Binary Tree.

The doubly linked list should be returned by taking the next pointer as right and the previous pointer as left.

You need to return the head of the Doubly Linked List.

For the given binary tree :

You need to return the head to the doubly linked list.
The doubly linked list would be: 1 2 3 4 5 and can be represented as: