Google L4 — strong start, fell short on the DP round

How I applied

A recruiter reached out on LinkedIn in December — a 15–16 minute call covering open roles, my background, a self-rating on DSA (I said ~8/10) and availability. Prep resources, a rough schedule and a mock-interview group followed.

Timeline

1. Recruiter screening call
2. Technical phone screen
3. 3 onsite technical rounds (virtual)
4. Googliness round

Round-by-round

1. Phone screen

Given a grid-like matrix plus a list of items and quantities, arrange items so similar ones end up adjacent row-wise or column-wise. It looked like a graph problem but was really about spotting the right pattern. Talked through the approach, coded it, discussed complexity — finished on schedule.

2. Onsite 1 — Dependency graph

Framed as managing storage disks and snapshots: a snapshot can only be removed once all disks (and disks derived from them) are deleted. Output a valid deletion order. Took some back-and-forth to understand, then solved it cleanly.

3. Onsite 2 — Dynamic programming

2D boxes of varying dimensions; find the maximum number that can be nested. A genuinely tough DP problem. I only reached brute force in the time available, and I knew while explaining it that it wasn't what they wanted.

4. Onsite 3 — Sorting / binary search

A neighbourhood of blocks with houses of different colours; rearrange so each block has uniquely coloured houses in sorted order. I got to something workable but not optimal. With a couple of minutes left it clicked that binary search was the key — too late.

5. Googliness

Relaxed conversation about background, projects and behavioural questions. A nice change of pace, and it went well.

Verdict

Not selected.