Expedia SWE — OA + 4 rounds (multi-company post); offer

I have learned a lot from this wonderful community, time to give back my bit to this awesome community.

Background:
Position: well known fintech product company
Experience: 6+ yrs
Questions solved: ~400: ~100 Easy, 250+ medium, 50 hard

Paypal: Reject
R0: Initial screening based on past projects
R1: Coin change problem, Questions on restful apis. [1hr]
R2: Database discussion on my current project [2hrs]
R3: System design round. [1hr]

UBER: Online Hackerrank Test: 2 Problems (Array based problem, Max Sliding window). R1 Machine coding: pub-sub library. R2 graphs: reconstruct itinerary (later converted to DFS). Turned down.

FaceBook: Phonescreen, 2 problems in 45 mins. Problem1: longest valid parenthesis (stacks). Problem2: comparator on strings to sort. Rejected citing code issues (poor variable names).

Google: July-Dec 2020. Phonescreen: sliding window / DP problem. Onsites 5 rounds — R1 arrays -> binary search (O(nlogn)->O(n)->O(logn)), R2 trees (hard), R3 trees medium->hard (sub-optimal red flag), R4 optimal value / binary search with follow-ups (readability feedback), R5 behavioral. Rejected.

Expedia: Offer

R0: Hackerrank Test
3problems:
2 easy array based questions.
1 Hard DP problem

R1: Problem solving round.
Easy question on trees.
Hard Level problem on Binary Search
Conceptually similar to https://leetcode.com/problems/divide-chocolate/

R2:
https://leetcode.com/problems/minimum-window-substring/
Slight modified version, with all character in same order as Input.

R3: Hiring Manager round with behavioral questions
Design Food delivery App.

R4 Design
Design rating & reviews system.

All interviews went great, was extended offer.