WEX | SDE 2 | Interview Experience
Summary
I completed three interview rounds for an SDE 2 position at WEX, solving several DSA problems, discussing OOP concepts, and presenting a high‑level design, with the entire process spanning multiple weeks.
Full Experience
Round 1 - DSA
I was asked to write pseudocode for 2 DSA problems.
I was able to complete the first problem, including optimizing the solution. For the second problem, I initially provided a solution with higher time complexity. After receiving a hint from the interviewer, I was able to arrive at the optimized solution.
Round 2 - DSA + OOPS
I was asked to write working code for 2 DSA problems.
I was able to solve both problems completely. After the coding section, the interviewer asked OOP concepts (4 core pillars) and SOLID principles.
Round 3 - Hiring Manager
After introductions, I was asked to design the architecture (HLD) of the project I had recently worked on in my current organization. The interviewer then evaluated my understanding of several fundamental concepts, including:
- API Design
- OOP - objects, classes, abstract classes, interfaces
- Exception handling
- Thread-safe Singleton design pattern
- SQL Joins
Finally, the round ended with some situational and behavioral questions.
Overall Experience
All the rounds were eliminatory and the interviews were scheduled once a week. Because of this, it took a considerable amount of time to complete the entire interview process.
Interview Questions (4)
Paint House
Given a row of houses, each house can be painted one of three colors. The cost of painting each house with a particular color is provided. Find the minimum total cost to paint all houses such that no two adjacent houses have the same color.
Candy
There are N children standing in a line, each with a rating. Distribute candies to the children such that each child gets at least one candy, and any child with a higher rating than an immediate neighbor receives more candies than that neighbor. Minimize the total number of candies distributed.
Word Search
Given a 2D board of characters and a word, determine if the word exists in the grid. The word can be constructed from letters of sequentially adjacent cells, where adjacent cells are horizontally or vertically neighboring. The same cell may not be used more than once.
Frequency of the Most Frequent Element
Given an integer array nums and an integer k, you can increment any element of the array by 1 at most k times in total. Return the maximum possible frequency of an element after performing the operations.