PayPal SSE 6YOE Reject Q4 2025
- Experience
- 6 years
- Posted
- 12 Jan 2026
Summary
My interview process for an SSE role at PayPal lasted two months and involved multiple rounds, including MCQs, coding, system design, and machine coding. Despite attempting all rounds, I was ultimately rejected, attributing the failure to an issue in my machine coding solution.
How it went
The overall process went for 2 months, thanks to the recruiter.
R1
MCQ:
- Given a basic spring boot, asked for the expected output.
- 401 response code related question
- Given a caching header, question was about s-maxage directive.
- Given an image, find the number of articulation points (separating vertex).
Coding question: Added at the end.
R2
Q1: You are given an array of distinct integers. Your task is to find the smallest absolute difference between any two elements in the array. Print all pairs of numbers that have this smallest difference. In each pair, the smallest number comes first. Print the pairs in ascending order. Example, input n equal to 4 elements and the numbers 6, 2, 4, 10. Output 2, 4, 2, 6. Explanation, the minimum absolute difference is 2, and the pairs with that difference are 2, 4 and 4, 6.
Q2. Piles of boxes: Alex has n piles of boxes with different heights. In each step, Alex can remove any number of boxes from the tallest pile to make its height equal to the next tallest pile. Determine the minimum number of steps needed to make all the piles the same height. Example, input boxes in piles equal to 5, 2, 1. Output 3. Explanation, remove three boxes from pile 0, remove one box from pile 1, remove one box from pile 0. Example 2, boxes in piles equal to 4, 5, 5, 2, 4. Output 6. The given input is in list of integer.
R3
Design Ride hailing app booking method.
R4
Machine coding splitwise: https://workat.tech/machine-coding/editorial/how-to-design-splitwise-machine-coding-ayvnfo1tfst6 Because of a faulty map.computeIfAbsent, the code didn't store transactions. And I didn't make it through.
R1 Coding question The interface Building includes the following methods: void floorCompleted(int floorNumber) void printStatus(int floorNumber); void printNumberOfFloors();
Develop two classes, School and Hospital, that implement the Building interface. The requirements for each class are as follows: Class School should have an integer array variable, floors. It should implement these methods: School(int n): • Initializes an empty array floors of length n, repsenting the number of floors in the school. • Sets all elements of floors to 0, indicating that none of the floors are completed. • Prints "A school is being constructed". void floorCompleted(int floorNumber): 49 Marks the floorNumber in the array floors as completed by setting it to 1. • Prints "Construction for floor number (floorNumber} completed in school" if floorNumber ≤ n. • Prints "Floor number (floorNumber) does not exist in school" if floorNumber > n. void printStatus(int floorNumber): • Checks the status of the specified floorNumber • Prints "Floor number (floorNumber} does not exist in school" if floorNumber > n • Prints "Construction for floor number (floorNumber) completed in school" if the status is 1. • Prints "Construction for floor number (floorNumber) not completed in school" if the status is 0. void printNumberOfFloors(): Prints "The school has (n) floors" to indicate the total number of floors in the school.
void printNumberOfFloors(): Prints "The school has (n) floors" to indicate the total number of floors in the school. Class Hospital should have an integer array variable, floors. It should implement these methods: Hospital(int n): • Initializes an empty array floors of length n, representing the number of floors in the hospital. ⚫ Sets all elements of floors to 0. indicating that none of the floors are completed. ⚫ Prints "A hospital is being constructed". void floorCompleted(int floorNumber): • Marks the floor Number in the array floors as completed by setting it to 1. • Prints "Construction for floor number (floorNurber) completed in hospital" if floorNumbers n. Prints "Floor number (floorNumber) does not exist in hospital" if floorNumber>n. void printStatus(int floorNumber): ⚫Checks the status of the specified floorNumber • Prints "Floor number (floorNumber) does not exist in hospital" if floorNumber> n. Prints "Construction for floor number (floorNumber) completed in hospital" if the status is 1. Prints "Construction for floor number (floorNumber) not completed in hospital" if the status is 0. void printNumberOfFloors(): • Prints "The hospital has (n) floors" to indicate the total number of floors in the hospital. Note: The provided locked code stub includes the Building Interface and validates the implementation of the School and Hospital classes.
Questions asked (8)
- 01
Spring Boot Expected Output
Other
Given a basic spring boot, asked for the expected output.
- 02
Caching Header s-maxage Directive
Other
Given a caching header, question was about s-maxage directive.
- 03
Articulation Points in a Graph
Data Structures & Algorithms · Hard
Given an image, find the number of articulation points (separating vertex).
- 04
Smallest Absolute Difference Pairs
Data Structures & Algorithms · Medium
You are given an array of distinct integers. Your task is to find the smallest absolute difference between any two elements in the array. Print all pairs of numbers that have this smallest difference. In each pair, the smallest number comes first. Print the pairs in ascending order. Example, input n equal to 4 elements and the numbers 6, 2, 4, 10. Output 2, 4, 2, 6. Explanation, the minimum absolute difference is 2, and the pairs with that difference are 2, 4 and 4, 6.
- 05
Piles of Boxes
Data Structures & Algorithms · Medium
Alex has n piles of boxes with different heights. In each step, Alex can remove any number of boxes from the tallest pile to make its height equal to the next tallest pile. Determine the minimum number of steps needed to make all the piles the same height. Example, input boxes in piles equal to 5, 2, 1. Output 3. Explanation, remove three boxes from pile 0, remove one box from pile 1, remove one box from pile 0. Example 2, boxes in piles equal to 4, 5, 5, 2, 4. Output 6. The given input is in list of integer.
- 06
Design Ride Hailing App Booking Method
System Design · Hard
Design Ride hailing app booking method.
- 07
Machine Coding: Splitwise
System Design · Hard
Open the problemMachine coding for Splitwise application.
- 08
Implement Building Interface: School and Hospital Classes
Data Structures & Algorithms · Easy
The interface Building includes the following methods: void floorCompleted(int floorNumber) void printStatus(int floorNumber); void printNumberOfFloors();
Develop two classes, School and Hospital, that implement the Building interface. The requirements for each class are as follows: Class School should have an integer array variable, floors. It should implement these methods: School(int n): • Initializes an empty array floors of length n, repsenting the number of floors in the school. • Sets all elements of floors to 0, indicating that none of the floors are completed. • Prints "A school is being constructed". void floorCompleted(int floorNumber): 49 Marks the floorNumber in the array floors as completed by setting it to 1. • Prints "Construction for floor number (floorNumber} completed in school" if floorNumber ≤ n. • Prints "Floor number (floorNumber) does not exist in school" if floorNumber > n. void printStatus(int floorNumber): • Checks the status of the specified floorNumber • Prints "Floor number (floorNumber} does not exist in school" if floorNumber > n • Prints "Construction for floor number (floorNumber) completed in school" if the status is 1. • Prints "Construction for floor number (floorNumber) not completed in school" if the status is 0. void printNumberOfFloors(): Prints "The school has (n) floors" to indicate the total number of floors in the school.
void printNumberOfFloors(): Prints "The school has (n) floors" to indicate the total number of floors in the school. Class Hospital should have an integer array variable, floors. It should implement these methods: Hospital(int n): • Initializes an empty array floors of length n, representing the number of floors in the hospital. ⚫ Sets all elements of floors to 0. indicating that none of the floors are completed. ⚫ Prints "A hospital is being constructed". void floorCompleted(int floorNumber): • Marks the floor Number in the array floors as completed by setting it to 1. • Prints "Construction for floor number (floorNurber) completed in hospital" if floorNumbers n. Prints "Floor number (floorNumber) does not exist in hospital" if floorNumber>n. void printStatus(int floorNumber): ⚫Checks the status of the specified floorNumber • Prints "Floor number (floorNumber) does not exist in hospital" if floorNumber> n. Prints "Construction for floor number (floorNumber) completed in hospital" if the status is 1. Prints "Construction for floor number (floorNumber) not completed in hospital" if the status is 0. void printNumberOfFloors(): • Prints "The hospital has (n) floors" to indicate the total number of floors in the hospital. Note: The provided locked code stub includes the Building Interface and validates the implementation of the School and Hospital classes.