Associate Software Engineer

You are given an array 'a' of size 'n'.

Print the Next Greater Element(NGE) for every element.

The Next Greater Element for an element 'x' is the first element on the right side of 'x' in the array, which is greater than 'x'.

If no greater elements exist to the right of 'x', consider the next greater element as -1.

For example:

Input: 'a' = [7, 12, 1, 20]

Output: NGE = [12, 20, 20, -1]

Explanation: For the given array,

- The next greater element for 7 is 12.

- The next greater element for 12 is 20. 

- The next greater element for 1 is 20. 

- There is no greater element for 20 on the right side. So we consider NGE as -1.

Given a linked list having two pointers in each node. The first one points to the next node of the list, however, the other pointer is random and can point to any node of the list or null. The task is to create a deep copy of the given linked list and return its head. We will validate whether the linked list is a copy of the original linked list or not.

A deep copy of a Linked List means we do not copy the references of the nodes of the original Linked List rather for each node in the original Linked List, a new node is created.

For example,

Random pointers are shown in red and next pointers in black.

You are given two strings S and X containing random characters. Your task is to find the smallest substring in S which contains all the characters present in X.

Example:

Let S = “abdd” and X = “bd”.

The windows in S which contain all the characters in X are: 'abdd', 'abd', 'bdd', 'bd'. 
Out of these, the smallest substring in S which contains all the characters present in X is 'bd'. 
All the other substring have a length larger than 'bd'.

A binary tree is a tree where each node has at most two children i.e left child and right child.

You are given a binary tree, where the structure of the node is as follow -:

class BinaryTreeNode {
 int data;      // Value of the node.
 BinaryTreeNode *left;  // Pointer to left child node.
 BinaryTreeNode *right; // Pointer to right child node.
 BinaryTreeNode *next;  // Pointer to next right node at same level. 
}

Your task is to connect all the adjacent nodes at the same level in the given binary tree. You can do this by populating each 'next' pointer to point to its next right node. If there is no next right node, the next pointer should be set to NULL. Initially, all the next pointers are set to NULL.

For Example:

Consider the figure shown below. The left part represents the initial binary tree and right part represents the binary tree after connecting adjacent nodes at the same level.

In the tree shown in the picture above -:
The ‘next’ pointer of the node having value 2 is connected to the node having value 3.
The ‘next’ pointer of the node having value 4 is connected to the node having value 5.
The ‘next’ pointer of the node having value 5 is connected to the node having value 6.
The ‘next’ pointer of nodes having value 1, 3, 6 will have a value NULL as there are no next right nodes in their cases.

Note:

1. The structure of the ‘Node’ of a binary tree is already defined. You should not change it.   
2. The root of the binary tree is known to you.  
3. There is at least one node in the given binary tree.
4. You may only use constant extra space.

You have been given a string ‘S' representing a number. Your task is to find the closest palindromic number from this integer represented by 'S'. The closest number is defined as the one for which the absolute difference between the given integer represented by 'S' and the palindrome number is minimum. If more than one number have the same difference then return the smaller integer.

Example:

Let 'S' is 121. Then the nearest integers are 111 and 131 which are palindrome. Both have the same absolute difference but 111 is smaller. Hence 111 is the answer.

What is CAP theorem?