I had a technical phone screen with Confluent. I was asked coding questions that I had seen in commonly asked interview questions.
Details
The coding questions were:
Sudoku solver.
Given a document list, where each document has an ID and a string containing many words, design a data structure to output a list of document IDs containing a given query word. Then, extend the design to handle queries like "word1 AND word2 OR word3". The solution involves treating AND/OR as non-leaf nodes in a binary tree and words as leaf nodes. You need to define the binary tree node and implement a function to traverse the tree and obtain the results. It is not necessary to build the binary tree from the query.