PayPal Interview Questions

Note: ensure you read the disclaimer on the previous page reading the accuracy and sourcing of these problems.

Validate Palindrome

Given a string str , can you write a method that will return True if is a palindrome and False if it is not? If you'll recall, a palindrome is defined as "a word, phrase, or sequence that reads the same backward as forward". For now, assume that we will not have input strings that contain spec...

Difficulty: 3/10

Find Shortest Palindrome Possible

We have a string str like the following: js const str "bubble" Find a way to convert it to a palindrome by inserting characters in front of it. Recall that a palindrome is defined as "a word, phrase, or sequence that reads the same backward as forward". What's the shortes...

Difficulty: 5/10

Find the Intersection of Two Linked Lists

Assume you have a Linked List implementation that has the following API: js prepend to start of list prepend val appends to end of list append val get an array of node values for testing toArray Can you write a method getIntersection list1, list2 to find the interse...

Difficulty: 4/10

Two Sum

This is a classic and very common interview problem. Given an array of integers, return the indices of the two numbers in it that add up to a specific "goal" number. Suppose we had an array 1, 3, 6, 7, 9 , and let's say our "goal" number was 10 . Our numbers to sum to it could be 3 and 7 , an...

Difficulty: 4/10

Find First Non-Repeating Character

You're given a string of random alphanumerical characters with a length between 0 and 1000 . Write a method to return the first character in the string that does not repeat itself later on. So if we had a string input of "asdfsdafdasfjdfsafnnunl'" , we can see there are multiple letters that...

Difficulty: 4/10

Dutch National Flag Problem

This problem is named the "Dutch national flag problem" because the flag of the Netherlands is comprised of the colors red, white, and blue in separate parts. Although we won't be using colors, the premise of the challenge is to develop a sorting algorithm that performs some form of separations of th...

Difficulty: 8/10

Sum of Perfect Squares

A perfect square is a number made by squaring a whole number. Some examples include 1 , 4 , 9 , or 16 , and so on because they are the squared results of 1 , 2 , 3 , 4 , etc. For example: 1 2 1 2 2 4 3 2 9 4 2 16 ... However, 15 is not a perfect square, bec...

Difficulty: 7/10

Lamps and Houses

On a given street, there's a bunch of houses and lamps nearby. It looks kind of like the following H being houses, L being lamps : L H L H H 0 1 2 3 4 We decide to represent this with two arrays: one being the positions of the houses, and the other the positions of the lamps. From the ...

Difficulty: 8/10

Linked List to Binary Search Tree

We're given a sorted singly linked list that is, a linked list made of nodes with no pointers to the previous node where the elements are already arranged in ascending order. js 9 2 3 5 9 Linked List Node Definition: function Node val this.val val this...

Difficulty: 7/10

Hoisting and Call Stack

Understanding Variable Scoping in JavaScript Let's dig into a fascinating JavaScript example to unravel the mystery of variable scoping. The Code Snippet Here's the code we'll be examining: javascript var numOfBeers 5 function getMoreBeers console.log 'I have this many beers: ...

Difficulty: 7/10

MERN Stack - Introduction

Introduction to MERN Stack The MERN stack is a powerful combination of technologies used to build full stack web applications. It consists of four main components: **MongoDB**: A NoSQL database used to store and manage data. **Express**: A web application framework for Node.js, used to cre...

Difficulty: 5/10

Real-World Project: Payment App

Introduction Welcome to the Payment App project! In this course, we will explore the development of a real world payment application using the MERN stack. This project aims to provide you with hands on experience in building a production ready payment app, covering various essential concepts and...

Difficulty: 5/10

People at PayPal Say

This information was sourced from reviews originally posted on Glassdoor.

Good compensation and benefits. Able to work on interesting and meaningful projects if you take initiative . Relatively relaxed and laidback - PTO, work from home, usually not too much work. This is said many times before, but quite a bureaucracy with office politics . Knowledge sharing is minimal if you don’t take the time to go out and learn it. Dependent on product managers you work with, but often will be brushed aside if your work is considered low priority. Many moving parts mean slowness, projects could drag very long if it involves work from other teams. Continue being champions for your employees. Many people do want to do meaningful work and stay busy but office politics often gets in the way of that.

Good work/life balance for teams that do not affect PayPal's bottom line. CEO is a great guy with a solid vision for the company. Good perks. Free soda, lots of events, technology training courses. If you can keep up with the high work demands, there is good upward mobility up to a certain point. Mediocre culture (perks != culture). Don't get caught up in the petty battles to impress your boss. Or, if you do, don't involve those working under you.

Work life balance (depends on team) Good pay (competitive in industry) Opportunities to move around internally Growing space of payments. Chaotic at times with constantly changing priorities. Vacation plan (unlimited but restricted to 3 weeks a year in practice). Blame games / politics. Not yet technology focused company (product / business driven). Genuine focus on technology/quality will help compete better with upcoming technology driven players in payments industry.

Brand value, market leader is payments , smart folks overall. Consistent growth. Campus in San Jose is nice. Some groups have good amount of fun. Too many reorgs in product area, ex eBay "leaders" killing the culture of bottom up innovation. Some key tech "gurus" prevent any kind of change in infrastructure. Please hire good leadership talent. These ex eBay guys, who used to address PayPal as "those guys" before the split, stuck promotion deals and came over to make a quick buck after the split. They don't really care much for the success Paypal. Currently they are all holed up CPI but they are starting to eye other groups now.