MTS 1

Given a string, determine if it is a palindrome, considering only alphanumeric characters.

Palindrome

A palindrome is a word, number, phrase, or other sequences of characters which read the same backwards and forwards.

Example:

If the input string happens to be, "malayalam" then as we see that this word can be read the same as forward and backwards, it is said to be a valid palindrome.

The expected output for this example will print, 'true'.

From that being said, you are required to return a boolean value from the function that has been asked to implement.

You are given an array/list ARR consisting of N integers. Your task is to find all the distinct triplets present in the array which adds up to a given number K.

An array is said to have a triplet {ARR[i], ARR[j], ARR[k]} with sum = 'K' if there exists three indices i, j and k such that i!=j, j!=k and i!=j and ARR[i] + ARR[j] + ARR[k] = 'K'.

Note:

1. You can return the list of values in any order. For example, if a valid triplet is {1, 2, -3}, then {2, -3, 1}, {-3, 2, 1} etc is also valid triplet. Also, the ordering of different triplets can be random i.e if there are more than one valid triplets, you can return them in any order.
2. The elements in the array need not be distinct.
3. If no such triplet is present in the array, then return an empty list, and the output printed for such a test case will be "-1".

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.

Given a binary tree with ‘root’. Your task is to find the sum of all the left leaf nodes.

Properties of leaf:-

In a binary tree, a leaf is a node such that it does not have any children. Node ‘1’ is always the root of the binary tree. Left leaves are those nodes that are the left child of their parent and a leaf node.

Example:

Let’s say you have a binary tree as follows:-

Node 4 and Node 5 are leaf nodes and left child of their parent. Node 6 is a leaf node but not the left child of its parent node 3. Therefore return ‘4+5= 9’ as the answer.

Note:

You do not need to print anything; it has already been taken care of. Just implement the function.

You are given two strings 'A' and 'B' of words. Your task is to find out the most frequent and lexicographically smallest word in string 'A', which is not present in string 'B'. If no such word is present in 'A', then return -1.

Note:

1. A word is a sequence of one or more lowercase characters.

2. Words are separated by a single whitespace character.

Example:

For the given string 'A' = “coding ninjas coding ninjas” and 'B' = “data structures and algorithms”, so both the word 'coding' and 'ninjas' are not present in string 'B' and occur two times each, but the word “coding” is lexicographically smaller than the word “ninjas”. So the answer is “coding”.

You are given a Singly Linked List of integers. Return true if it has a cycle, else return false.

A cycle occurs when a node's next points back to a previous node in the list.

Example:

In the given linked list, there is a cycle, hence we return true.

Tell me about yourself.

Why do you want to join us?

Where do you see yourself in 5-10 years?