Interview Experience: Google | L3 Web Solutions Engineer (GTech)

Overview

• Role: Web Solutions Engineer (L3)
• Organization: GTech
• Duration: ~60 Minutes
• Focus: Data Structures, Algorithms, and Web Internals

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Data Structures & Algorithms

The Visibility Problem

Given an array representing the heights of people, determine how many people are visible to the last person in the array.

Rule: Person A is visible to Person B if there is no one between them who is taller than both Person A and Person B.

Example:

• Input: [1, 10, 5, 7, 6, 3, 2, 4]
• Output: 5 (The people with heights 2, 3, 6, 7, and 10 are visible to 4)

Follow-up:
Find the number of visible people for every person in the list (not just the last one).

Goal: Implement an optimized solution with $O(n)$ time complexity for both cases.

Web Technology

How would you optimize a website across the following three layers(Frontend, Backend, Database)?

Explain the process of what happens from the moment a user types a URL into the browser until the page is fully rendered.

Compare and contrast Server-Side Rendering (SSR) vs. Client-Side Rendering (CSR).

Section 3: Bonus / Quickfire Question

Problem: Transition Peak Finding

You are given an array that is a mixture of True and False values.

• The array always starts with True.

* The array always ends with False.

• Task: Find any index $i$ such that arr[i] == True and arr[i+1] == False.

Goal: Implement an optimized solution (Binary Search) with $O(\log n)$ time complexity.