Google Coding & Algorithms Interview Questions

Preparing for Google Coding & Algorithms interview questions means getting ready for a rigorous, process-driven evaluation that emphasizes clean problem solving, clear communication, and algorithmic depth. Google tends to focus on core data structures and algorithmic patterns—arrays and strings, trees and graphs, dynamic programming, hashing, and complexity trade-offs—while also assessing how you reason through edge cases, test your ideas, and write production-minded code in a collaborative environment. Expect live coding on a shared document during screens and multiple 45‑minute coding rounds in onsite or virtual loops, with system design and behavioral evaluations added for more senior roles. Effective interview preparation balances breadth and depth: practice medium-to-hard algorithmic problems under timed conditions, review core computer science fundamentals, and rehearse explaining tradeoffs and correctness aloud. Work on structured problem walkthroughs, mock interviews that simulate Google’s collaborative doc format, and concise post-solution optimizations. Also prepare concise, impact‑focused stories for the behavioral round and plan a realistic multi-week schedule that includes focused drills, full mock loops, and targeted review of persistent weak spots.

224 Questions 1 Company08.01.2026
Showing 20 results
Role
Google logo
Google
Medium
Software Engineer

Find Players with Uniquely Determined Rankings

Find Players with Uniquely Determined Rankings Problem There are n players numbered 0 through n - 1. Each result (winner, loser) states that the winne...

Coding & Algorithms
1
0
10 people solved
Apr 19, 2026
Google logo
Google
Hard
Software EngineerSenior+

Convert Valid Snake Case to Lower Camel Case

Convert Valid Snake Case to Lower Camel Case Given a valid snake-case identifier, convert it to lower camel case. The input consists of one or more lo...

Coding & Algorithms
3
2
18 people solved
Apr 16, 2026
Google logo
Google
Medium
Software Engineer

Design an elevator control system

Design the software for a multi-elevator control system in a high-rise building. Specify classes, scheduling algorithms for car assignments, handling ...

Coding & Algorithms
9
0
106 people solved
Sep 6, 2025
Google logo
Google
Medium
Software Engineer Locked

Implement text wrapping, waitlist, and intervals

This question evaluates skills in string parsing and word-wrapping logic, data-structure design for FIFO queue management and deletions, and interval ...

Coding & Algorithms
19
0
152 people solved
Feb 12, 2026
Google logo
Google
Easy
Software Engineer Locked

Compute decayed power levels in a graph

This question evaluates knowledge of graph algorithms and distance-based propagation, testing concepts such as shortest-path distance computation, mul...

Coding & Algorithms
18
0
151 people solved
Feb 12, 2026
Google logo
Google
Hard
Software EngineerNew Grad Locked

Compute Turnstile Crossing Times

This question evaluates proficiency in queue simulation, event-driven scheduling, and handling priority and tie-breaking rules while achieving linear ...

Coding & Algorithms
5
1
50 people solved
May 4, 2026
Google logo
Google
Medium
Software Engineer

Find the Longest Consecutive Path in a Binary Tree

Given a binary tree, return the length of the longest downward path where each child value is exactly one greater than its parent value. Nodes have va...

Coding & Algorithms
0
0
6 people solved
Apr 28, 2026
Google logo
Google
Medium
Software Engineer

Return the Most Frequent Values in an Array

Given a non-empty integer array, return the k values that appear most frequently. Ties are broken by smaller value first. Implement: `python def top_k...

Coding & Algorithms
2
1
16 people solved
Apr 28, 2026
Google logo
Google
Medium
Software Engineer

Determine if a 14-tile hand is winning

You are given an integer array tiles of length 14 representing a Mahjong-like hand. Each integer is a tile value from 1 to 9 (single suit). You may re...

Coding & Algorithms
20
0
203 people solved
Mar 9, 2026
Google logo
Google
Medium
Software EngineerNew Grad

Count Good Numbers up to a Limit

Count Good Numbers up to a Limit A positive integer is good when all of the following hold: 1. Its decimal representation contains no digit 0. 2. No d...

Coding & Algorithms
1
0
10 people solved
Apr 26, 2026
Google logo
Google
Medium
Software EngineerNew Grad

Find the Longest Momentum-Aware Water Path

Find the Longest Momentum-Aware Water Path Given an m × n integer height grid, find the maximum number of cells in a valid path. A path may start at a...

Coding & Algorithms
1
0
10 people solved
Apr 26, 2026
Google logo
Google
Medium
Software EngineerIntern Locked

Match people to questions using tags and priorities

This question evaluates competencies in bipartite matching and combinatorial optimization, along with practical data-structure design for scalable tag...

Coding & Algorithms
11
0
189 people solved
Dec 27, 2025
Google logo
Google
Medium
Software Engineer

Design server allocation for multi-type nodes

Design a service to manage a large pool (about 100, 000) of server nodes. Each node can satisfy multiple instance types; clients call getServer(reqNum...

Coding & Algorithms
8
0
126 people solved
Sep 6, 2025
Google logo
Google
Medium
Software EngineerNew Grad

Track Island Counts as Land Is Added

Track Island Counts as Land Is Added Problem Implement trackIslandCounts(grid, additions) -> counts. grid is a rectangular array containing 0 for wate...

Coding & Algorithms
0
0
8 people solved
Dec 8, 2025
Google logo
Google
Medium
Data Scientist Locked

Implement sampling and subarray algorithms

Solve uniform 2D square sampling and longest increasing contiguous subarray. The solution maps Uniform(0,1) to Uniform(-1,1), proves uniformity by ind...

Coding & Algorithms
8
0
82 people solved
Mar 9, 2025
Google logo
Google
Medium
Software Engineer Locked

Solve Shortest Paths and Rental Allocation

This question evaluates understanding of shortest-path algorithms and reachability in weighted graphs (including directed vs. undirected handling and ...

Coding & Algorithms
6
0
45 people solved
Apr 12, 2026
Google logo
Google
Medium
Software EngineerNew Grad

Solve Two Array Optimization Problems

You are given two coding problems from the same interview round. Problem 1: Split a gold chain fairly An array weights represents the weights of conse...

Coding & Algorithms
22
1
126 people solved
Apr 11, 2026
Google logo
Google
Medium
Machine Learning Engineer Locked

Implement substring search and weighted sampling

This question evaluates algorithm design and analysis skills across string processing (efficient substring search) and randomized/data-structure techn...

Coding & Algorithms
13
0
114 people solved
Mar 30, 2026
Google logo
Google
Hard
Software EngineerSenior+ Locked

Solve order-statistics and XOR-triplet problems

This multi-part question evaluates skills in order-statistics and efficient counting for array inversion-like problems, alongside bitwise manipulation...

Coding & Algorithms
21
0
186 people solved
Jan 22, 2026
Google logo
Google
Medium
Software Engineer Locked

Determine Whether a Word Exists in a Graph

This question evaluates proficiency in graph algorithms and backtracking techniques, including traversal strategies, cycle avoidance, and state manage...

Coding & Algorithms
6
2
37 people solved
May 2, 2026

Frequently Asked Questions

How difficult are Google Coding & Algorithms interviews?
Google coding and algorithms rounds are typically medium-to-hard on a LeetCode-style scale, with difficulty increasing by level and role. Phone screens usually target solid problem-solving and clean coding at a medium-to-hard level, while onsite/loop rounds expect more polished, optimized solutions and harder algorithmic thinking for senior roles. Interviewers evaluate algorithm design, correct and maintainable code, complexity trade-offs, and communication. Expect follow-ups that push for edge-case handling and performance improvements. Preparing with progressively harder problems and mock interviews helps bridge the gap to the typical onsite bar.
What is the typical Google interview process and where do Coding & Algorithms questions appear?
The process commonly starts with a recruiter screen, followed by one or two technical phone/video screens that include live coding on a shared environment, and then a virtual or onsite loop of four to six interviews that mix coding, system design (for senior candidates), and behavioral assessments. Coding and algorithms questions appear in the phone screens and in multiple onsite rounds, often as one to two algorithmic problems per technical interview. New graduate roles may include an online assessment stage. The shared-coding document or collaborative pad is a common environment for real-time problem solving.
How long should I prepare for Google Coding & Algorithms interviews?
A focused preparation timeline often ranges from six to eight weeks for candidates with solid fundamentals, and from two to four months for those rebuilding skills or targeting senior levels. Early weeks should refresh data structures, complexity analysis, and basic algorithms; middle weeks should emphasize consistent timed practice of medium to hard problems and pattern recognition; final weeks should include mock interviews, whiteboard or shared-doc practice, and review of common failure cases. Allocate regular, spaced practice and iterative feedback to close gaps, and simulate the exact environment (no IDE, shared doc) before real interviews.
What key subtopics within Coding & Algorithms should I focus on for Google interviews?
Focus on core data structures (arrays, strings, linked lists, stacks, queues, trees, graphs, heaps, and hash tables) and algorithms (sorting, searching, DFS/BFS, shortest paths, topological sorts, greedy strategies, and dynamic programming). Master complexity analysis, common patterns like two-pointers, sliding window, recursion/backtracking, and graph traversal. Also practice windowed aggregates, prefix sums, CTE-like problem decomposition in coding interviews, handling NULLs/edge cases, and thinking about performance trade-offs. Clean, testable code and the ability to explain correctness and runtime are as important as finding a working solution.
What standout tips and common pitfalls should I know when preparing for Google Coding & Algorithms interviews?
Standout tips include asking clarifying questions before coding, outlining the approach and complexity up front, writing a correct simple solution before optimizing, and walking through test cases aloud. Practice in a shared-doc or whiteboard style to mirror the interview environment and time-box your practice. Common pitfalls are not communicating thought process, ignoring constraints and edge cases, prematurely optimizing without a correct baseline, and submitting untested code. Also avoid verbose or unreadable code; prioritize clarity. Mock interviews with feedback are one of the fastest ways to fix these recurring mistakes.

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