Technical Interview — DSA
Additional Context: I interviewed for Google L3/L4. The process consisted of 4 rounds.
Round 1:
Q1: Given a binary tree, return all leaf nodes having the maximum root-to-leaf path value. I solved it using a preorder traversal. Q2: Given a dictionary of strings, find the longest valid word. A word is valid if repeatedly removing exactly one character produces another word in the dictionary, eventually reaching a single-character word. I initially proposed backtracking and then optimized it using memoization to avoid exploring the same word repeatedly.
A hard DSA problem involving maximum total. I was able to derive and implement the optimized approach within the given time.
Behavioral questions, including situations involving conflict with a coworker and other situational/behavioral questions.
Technical/DSA interview. The interviewer experience was difficult, and I was ultimately down-leveled to L3 despite initially interviewing for L3/L4.
Tips: Strong DSA preparation is essential, especially trees, backtracking, dynamic programming/optimization, and being able to improve a brute-force solution through memoization or other optimizations. Behavioral preparation is also important for the Googlyness round.