Senior Software Engineer

You are given a string ‘STR’ of size ‘N’ and an integer ‘M’ (the number of rows in the zig-zag pattern of ‘STR’). Your task is to return the string formed by concatenating all ‘M’ rows when string ‘STR’ is written in a row-wise zig-zag pattern.

Example:

N = 12, M = 3 and STR = ‘CODINGNINJAS’

There are three rows (‘M = 3’) in the zig-zag pattern. Row one contains ‘CNN’, row two contains ‘OIGIJS’, and row three contains ‘DNA’. After concatenating the three rows, we get the string ‘CNNOIGIJSDNA’. So, the answer is ‘CNNOIGIJSDNA’.

Note:

1. The string ‘STR’ consists of capital letters only (i.e., characters from ‘A-Z’).

Ninja loves beautiful numbers and also has two integers, ‘L’ and ‘R’, denoting an interval [L, R].

Given the interval [L, R], Ninja wants you to find the number of Beautiful numbers in the interval.

A Beautiful Number is a number that:

Becomes 1 by repeatedly replacing the number with the sum of squares of its digits.

If the number does not become 1, then it’s not a Beautiful Number.

For example, given interval = [1, 3]

We see that 1 is a Beautiful Number but 2,3 are not. Hence the answer is 1.

Output the single integer, the sum of all Beautiful Numbers in the given range.

Example:

Input: ‘L’ = ‘1’ ,  'R' = ‘3’

Output: 1

As ‘1’ is the only Beautiful Number.

3 is not Beautiful as, 
3 -> 9
9 -> 81
81 -> 65
65 -> 61 … and so on
It can be shown that we cannot get 1. 

You are given two sorted linked lists. You have to merge them to produce a combined sorted linked list. You need to return the head of the final linked list.

Note:

The given linked lists may or may not be null.

For example:

If the first list is: 1 -> 4 -> 5 -> NULL and the second list is: 2 -> 3 -> 5 -> NULL

The final list would be: 1 -> 2 -> 3 -> 4 -> 5 -> 5 -> NULL

You are given an array/list ‘ARR’ of ‘N’ positive integers and an integer ‘K’. Your task is to check if there exists a subset in ‘ARR’ with a sum equal to ‘K’.

Note: Return true if there exists a subset with sum equal to ‘K’. Otherwise, return false.

For Example :

If ‘ARR’ is {1,2,3,4} and ‘K’ = 4, then there exists 2 subsets with sum = 4. These are {1,3} and {4}. Hence, return true.

Design a chatbot

1. Describe a project where you had to take the initiative?

 2. At PayPal, we are proud of our ability to stay one step ahead of our competitors. How will you contribute to this trend?

 3. Tell me what others would say about you.

 4. Why do you want to join PayPal?