Zensar Technologies Interview Question
Technical Questions: Algorithms: How would you find the longest substring without repeating characters? Can you explain the difference between a binary search tree and a balanced tree? Core Java: What are the key differences between an interface and an abstract class? How does garbage collection work in Java? SQL: Write a query to find the second-highest salary from an employee table. How do joins work in SQL? Can you explain the difference between INNER JOIN and LEFT JOIN? Behavioral/Soft Skills Questions: Tell us about a challenging project you worked on. How did you handle the obstacles? How do you prioritize tasks when working under a tight deadline? These questions cover both technical and soft skills to test your overall abilities.
Interview Answer
Anonymous
1. Longest Substring Without Repeating Characters (Algorithms) Answer: I started by explaining the sliding window technique. I used two pointers to maintain a window of characters and a set to keep track of unique characters. As I moved the right pointer to expand the window, I checked if the character already existed in the set. If it did, I moved the left pointer until the duplicate was removed. This ensured an optimal time complexity of O(n).