Google L4 Onsite Blr - experience June 2026
Summary
I completed the onsite interview for a L4 role at Google in Bangalore, which included two technical rounds (R3 DSA and R4 3D DP).
Full Experience
Recently I interviewed for L4 - Google (blr onsite). I cleared R1 and Goolyness (virtual) then I was called for onsite - R3 and R4.
R3 - DSA
Question was about movies with similar movies list. We need to create something like top k recommendation whenever someone clicks on any movie like Youtube. The person interviewing me was from youtube india team. Input - List of lists so I thought of Graph and minimum path first but eventually for better optimisation - I created DSU keeping similar movies list as value of every node.
R4 - 3D - DP
It was a 3D DP question - crazy optimisation for F1 racing tyre quality score and more factors.
Last round went too intense.
Good Luck!
Interview Questions (1)
Top-K Movie Recommendation based on Similar Movies
Given a collection of movies where each movie has a list of similar movies, design a system that returns the top‑K recommended movies whenever a user clicks on a particular movie. The input is provided as a list of lists representing similarity relationships between movies. The solution should efficiently retrieve the top‑K recommendations for the clicked movie.
Candidate approach: Initially considered modeling the similarity data as a graph and computing shortest paths, but later optimized by using a Disjoint Set Union (DSU) structure where each node stores the list of similar movies as its value, enabling fast union and retrieval operations.