EPAM | Senior Software Developer | Hyderabad | Dec 2023 [Passed]

Round 1

Questions:

• Introduction: Gave a brief introduction about my experiences.

• Java-Related Questions:

  • JVM, Heap memory, and Stack memory
  • Runtime polymorphism
  • Hierarchy of the collection framework
  • Difference between a Map and TreeSet, internal working of HashMap
  • Immutability of strings in Java, difference between StringBuffer and StringBuilder
  • Streams and filters (though no further questions as I wasn't familiar with them)
  • Functional interfaces
  • SOLID Principles, particularly the Liskov substitution principle
  • Data structures in use in code
  • Multi-threading and ExecutorService
  • Adapter pattern
  • Builder pattern
  • Asked about why we were using Camunda workflows and if we had evaluated other options like Netflix conductor
  • Reason for using Cosmos DB

• DSA Questions:

  1. Combination Sum-like problem: Instead of candidates, the number K was given, and all numbers from 1 through K were candidates. Similar to: Combination Sum
  2. All Nodes Distance K in Binary Tree: Provided a graph-based approach which was correct, but the interviewer wanted another approach. Most time was spent on the first question, so didn't get to code this.