BlackRock Interview Questions

How do you detect a cycle in a linked list?

You are given 8 identical-looking balls. Seven of the balls are equal in weight, and one of them is lighter. How would you efficiently find the lighter ball?

How can you join two database tables in SQL without using the JOIN keyword?

Implement a hashMap data structure. What are the differences between a hashMap and a treeMap?

1. What is the difference between shallow copy and deep copy in C++? 2. Implement a class using the singleton pattern in Java. 3. Find the first common ancestor of two nodes in a binary search tree (BST).