Google SWE Intern interview questions

Trees and graphs. Practice them very much.

### **1. Online Assessment:** - **Question 1:** Given an array of integers, return the length of the longest subarray with a sum equal to zero. - **Question 2:** Given a matrix of `m x n` dimensions, find the number of ways to reach the bottom-right corner from the top-left corner, where you can only move down or right. - **Question 3:** Implement a function to detect if a cycle exists in a directed graph. ### **2. Phone Screen:** - **Question:** You are given a list of projects and dependencies between them (each dependency is a pair of projects where the first project is dependent on the second). Write a function to find an order in which to complete all the projects. (Topological Sort) ### **3. Onsite Interviews:** #### **Round 1: Data Structures & Algorithms** - **Question 1:** Given a binary tree, find the maximum path sum. The path may start and end at any node in the tree. - **Question 2:** Implement an LRU (Least Recently Used) cache system with `get` and `put` operations in O(1) time. #### **Round 2: System Design** - **Question:** Design a scalable chat application. Discuss how you would handle real-time messaging, message storage, and delivery guarantees in a distributed system. #### **Round 3: Behavioral Interview** - **Question 1:** Tell me about a time when you had to work with a difficult team member. How did you handle the situation, and what was the outcome? - **Question 2:** Describe a situation where you faced a significant challenge in a project. How did you overcome it? #### **Round 4: Coding Challenge** - **Question:** Given a string of digits, return all possible valid IP addresses that can be formed by inserting dots into the string. (e.g., "25525511135" can be turned into "255.255.11.135", "255.255.111.35") #### **Round 5: Googleyness & Leadership** - **Question 1:** How have you demonstrated leadership in a project that you were passionate about? What impact did your leadership have on the project's success? - **Question 2:** Tell me about a time when you had to make a decision with limited information. How did you approach the situation? These questions are designed to test a candidate's technical skills, problem-solving ability, and how well they fit within the company culture.