Applied via referral.

Round 1 : OA (Dont remember questions but it was simple)

Round 2 : DSA

https://leetcode.com/problems/longest-path-with-different-adjacent-characters/description/

Round 3 : LLD

Design a pub-sub queue, where multiple messages are being published and multiple consumers can consume it. Order should be maintained for message processing ie the message that came first should be processed first.