SDE - 1

You have been given the prices of 'N' stocks in an array where each array element represents the stock price for that day. You need to find the maximum profit which you can make by buying and selling the stocks. You may make as many transactions as you want but can not have more than one transaction at a time i.e, if you have the stock, you need to sell it first, and then only you can buy it again.

You have a binary tree of 'N' unique nodes and a Start node from where the tree will start to burn. Given that the Start node will always exist in the tree, your task is to print the time (in minutes) that it will take to burn the whole tree.

It is given that it takes 1 minute for the fire to travel from the burning node to its adjacent node and burn down the adjacent node.

For Example :

For the given binary tree: [1, 2, 3, -1, -1, 4, 5, -1, -1, -1, -1]
Start Node: 3

    1
   / \
  2   3
     / \
    4   5

Output: 2

Explanation :
In the zeroth minute, Node 3 will start to burn.

After one minute, Nodes (1, 4, 5) that are adjacent to 3 will burn completely.

After two minutes, the only remaining Node 2 will be burnt and there will be no nodes remaining in the binary tree. 

So, the whole tree will burn in 2 minutes.

You are given a binary tree consisting of 'n' nodes.

Convert the given binary tree into a linked list where the linked list nodes follow the same order as the pre-order traversal of the given binary tree.

Use the right pointer of the binary tree as the “next” pointer for the linked list and set the left pointer to NULL.

Use these nodes only. Do not create extra nodes.

Example :

Input: Let the binary be as shown in the figure:

Output: Linked List: 15 -> 40 -> 62 -> 10 -> 20 -> NULL

Explanation: As shown in the figure, the right child of every node points to the next node, while the left node points to null.

Also, the nodes are in the same order as the pre-order traversal of the binary tree.

Communication between two processes. (Learn)

Given a number ‘grayNumber’. Find the gray code sequence.

Conditions for a gray code sequence :

1. Gray code sequence contains numbers from 0 to 2^'grayNumber'-1 in bit/binary form.
2. Two consecutive gray code sequence numbers only differ by 1 bit.
3. Gray code sequence must start with 0.

Example :

Given 'grayNumber' : 2.

As depicted from above image, the gray code sequence is 0,1,3,2.

Note :

1. The output sequence must contain the decimal representation of numbers instead of the binary form.
2. There can be multiple answers print anyone.