System Engineer

You are given an array ‘Arr’ consisting of ‘N’ distinct integers and a positive integer ‘K’. Find out Kth smallest and Kth largest element of the array. It is guaranteed that K is not greater than the size of the array.
Example:
Let ‘N’ = 4, ‘Arr’ be [1, 2, 5, 4] and ‘K’ = 3. 
then the elements of this array in ascending order is [1, 2, 4, 5]. Clearly, the 3rd smallest and largest element of this array is 4 and 2 respectively.

You are given a string 'STR' of length 'N'. You need to return a string that will contain all the characters present at the prime indices of the original string. The relative order of characters in the new string should be exactly the same as it was in the original string.
Note:
1. Prime indices are those indices that are prime numbers i.e. all the numbers except 0 and 1 which are divisible by 1 and the number itself. For eg. If a character is at index 5 in some string, then it is at a prime index, as 5 is a prime number.

2. The given string may consist of characters ‘a’-’z’, ‘A’-’Z’, ‘0’-’9’ at any place.

3. The given string follows 0-based indexing. So, assume that the first character of the given string is at index 0.

Tip 1 : Be prepared and convey with proper simple sentences.
Tip 2 : Giving examples for each question.
Tip 3 : Being honest and genuine.