Wissen Technology Interview Experience (2023)

In technical round -1 & round-2, they asked me questions based on JAVA, OOPS, DBMS, OS, SQL, and DSA.

1. What is the definition of Abstraction?
2. Explain abstraction with real-life examples.
3. What is Encapsulation? Explain it with an example. How it differs from abstraction.
4. What is Polymorphism? Type of polymorphism and explain with example.
5. What is a composition in JAVA?
6. Explain composition with a real-life example and write code for that example.
7. Does Java support multiple inheritance?
8. What is inheritance in JAVA? Type of inheritance?
9. Can we achieve multiple inheritance in JAVA, How?
10. What is called pure abstraction?
11. Write a code for multilevel inheritance.
12. What is a diamond problem in Java?
13. Write code for TWO SUM.
14. Write code to find the middle of the linked list.
15. Write code for removing the duplicate string.
16. Write code for finding the first non-repeating element in an array.
17. Write code for finding the right view of a binary tree.
18. Write code for finding the path of a tree.
19. Write code for merge two linked list.
20. Write code for detect a loop in linked list.