SDE - 1

You are given a string 'str' of length 'N'.

Your task is to return the longest palindromic substring. If there are multiple strings, return any.

A substring is a contiguous segment of a string.

For example :

str = "ababc"

The longest palindromic substring of "ababc" is "aba", since "aba" is a palindrome and it is the longest substring of length 3 which is a palindrome. 

There is another palindromic substring of length 3 is "bab". Since starting index of "aba" is less than "bab", so "aba" is the answer.

You are given an array of strings 'ARRSTR[]' of size 'N' and a character 'C'. Your task is to sort the 'ARRSTR[]' according to the new alphabetical order that starts with the given character 'C'.

Note:

1) The character ‘C’ is a lowercase English alphabet that is given as input.
2) For example, if the character is 'C' is "d" then, the alphabetical order starts with "d" will look like {d,e,f,....,y,z,a,b,c}.
3) Every string in the array consists of only lowercase English alphabets.

Ninja is given a binary search tree and an integer. Now he is given a particular key in the tree and returns its ceil value. Can you help Ninja solve the problem?

Note:

Ceil of an integer is the closest integer greater than or equal to a given number.
For example:
arr[] = {1, 2, 5, 7, 8, 9}, key = 3.
The closest integer greater than 3 in the given array is 5. So, its ceil value in the given array is 5.

Given a Binary Search Tree (BST) and a range [min, max], remove all keys which are outside the given range. The modified tree should also be BST.