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Decode the Coding Interview in Ruby: Real-World Examples Save
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The ultimate guide to Ruby interviews. Developed by FAANG engineers, practice with real-world interview questions from top companies. Prep faster and get interview-ready in just a few hours.
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Preparing for coding interviews has become a daunting task. Trying to solve enough practice questions and remember solutions can feel impossible.
Fortunately, the best way to be successful in the coding interview is not to just grind through problems. The best way is to develop the skills to break down a new problem and deploy the right tools to come up with a solution.
That’s why in this course, you’ll prepare for coding interviews by tackling real world problems faced by tech companies. When you solve real problems related to real projects (for example, paginating attendees in a Zoom call), not only will you have more fun preparing, but you’ll also have an easier time remembering what you’ve learned.
After each project, we’ll also show you what kinds of interview problems you’ll now be able to solve using the techniques you just applied, so that your knowledge is adaptable to new problems.
(This course is also available in Rust, Java, C++, C#, Go, Python, Elixir, Scala, Swift, Kotlin and JavaScript.)
Preparing for coding interviews has become a daunting task. Trying to solve enough practice questions and remember solutions can...Show More
WHAT YOU'LL LEARN
Get hands on practice in preparing for coding interviews by tackling real world problem.
Prepare for interviews by solving the frequently asked coding question at companies like FAANG.
Perform an in-depth analysis of commonly asked coding interview problems.
Learn to map real-world problems to actual interview questions.
Get hands on practice in preparing for coding interviews by tackling real world problem.
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Content
1.
✨Getting Started
2 Lessons
Get familiar with coding interview essentials, tackling real-world problems, and key patterns.
2.
Netflix
26 Lessons
Walk through Netflix feature implementations, optimizing search, recommendations, and user session handling.
Project Description For NetflixFeature #1: Group Similar TitlesFeature #2: Fetch Top MoviesFeature #3: Find Median AgeFeature #4: Popularity AnalysisFeature #5: Fetch Most Recently Watched TitlesFeature #6: Fetch Most Frequently Watched TitlesFeature #7: Browse RatingsFeature #8: Verify User SessionFeature #9: Movie Combinations of a GenreFeature #10: Calculate Median of Buffering EventsFeature #11: Generate Movie Viewing OrdersFeature #12: Maintain Continue Watching BarWhat Did We Learn?DIY: Group AnagramsDIY: Merge K Sorted ListsDIY: Find Median from a Data StreamDIY: Monotonic ArrayDIY: LRU CacheDIY: LFU CacheDIY: Min StackDIY: Validate Stack SequencesDIY: Letter Combinations of a Phone NumberDIY: Sliding Window MedianDIY: PermutationsDIY: Maximum Frequency Stack
3.
22 Lessons
Examine advanced coding challenges and solutions, enhancing Facebook's features for integration and user experience.
Project Description for FacebookFeature #1: Friend CirclesFeature #2: Copy ConnectionsFeature #3: Find Story IDFeature #4: Request LimiterFeature #5: Flag WordsFeature #6: Combine Similar MessagesFeature #7: Divide PostsFeature #8: Overlapping TopicsFeature #9: Recreating the Decision TreeWhat Did We Learn?DIY: Number of IslandsDIY: Number of ProvincesDIY: Number of Connected Components in an Undirected GraphDIY: Clone Directed GraphDIY: Search in Rotated Sorted ArrayDIY: Logger Rate LimiterDIY: Expressive wordsDIY: Group Shifted StringsDIY: Divide ChocolateDIY: Minimum Window SubstringDIY: Construct a Binary Tree from Preorder and Inorder Traversal
4.
Search Engine
22 Lessons
Enhance your skills in developing search engine features through efficient data structures and algorithms.
Project Description for Search EngineFeature #1: Store and Fetch WordsFeature #2: Design Search Autocomplete SystemFeature #3: Add White Spaces to Create WordsFeature #4: Suggest Possible Queries After Adding White SpacesFeature #5: Calculate the Search Ranking FactorFeature #6: Reorganizing Search ResultsFeature #7: Find Searching TimeFeature #8: Distributed Process CoordinatorFeature #9: Finding Minimum ServersWhat Did We Learn?DIY: Implement TrieDIY: Suggest Relevant SentencesDIY: Word BreakDIY: Word Break IIDIY: Product of Array Elements Except ItselfDIY: Reorganizing a StringDIY: Exclusive Time of FunctionsDIY: Snapshot ArrayDIY: Coin ChangeDIY: Coin Change 2DIY: Combination Sum
5.
Google Calendar
17 Lessons
Solve problems in Google's calendar app, enhancing scheduling, conflict management, and productivity features.
Project Description for Google CalendarFeature #1: Find Meeting RoomsFeature #2: Show Busy ScheduleFeature #3: Check if Meeting is PossibleFeature #4: Schedule a New MeetingFeature #5: Find Common Meeting TimesFeature #6: Find Two Sets of Consecutive DaysFeature #7: Longest Busy PeriodWhat Did We Learn?DIY: Find Interval SetsDIY: Merge IntervalsDIY: My CalendarDIY: Insert IntervalDIY: Interval Lists IntersectionDIY: Employee Free TimeDIY: Find Two Non-Overlapping Subarrays Each with Target SumDIY: Longest Consecutive Sequence
6.
Stock Scraper
13 Lessons
Follow the process of designing a stock scraper, DOM traversal, and analyzing stock data efficiently.
Project Description for Stock ScraperFeature #1: Traversing DOM TreeFeature #2: Locating Stock DataFeature #3: Traversing DOM Tree IIFeature #4: Maximum ProfitWhat Did We Learn?DIY: Binary Tree Level Order TraversalDIY: Lowest Common Ancestor of a Binary TreeDIY: Lowest Common Ancestor of a Binary Tree IIIDIY: Populating Next Right Pointers in Each NodeDIY: Populating Next Right Pointers in Each Node IIDIY: Maximum SubarrayDIY: Best Time to Buy and Sell Stock
7.
UBER
18 Lessons
Master the steps to optimize Uber's driver allocation, route planning, fares, and carpool options.
Project Description for UberFeature #1: Select Closest DriversFeature #2: Path CostFeature #3: Plot and Select PathFeature #4: Fare in WordsFeature #5: Uber PoolFeature #6: Longest RouteFeature #7: Highest RankFeature #8: Optimal PathWhat Did We Learn?DIY: K Closest Points to OriginDIY: Trapping RainwaterDIY: Evaluate DivisionDIY: Integer to English WordsDIY: Random Pick with WeightDIY: Diameter of Binary TreeDIY: Kth Largest Element in an ArrayDIY: Minimum Path Sum
8.
Amazon
34 Lessons
Step through Amazon’s coding challenges, covering recommendations, logistics, price filtering, and more.
Project Description for AmazonFeature #1: Suggest Items for Free DeliveryFeature #2: Suggest Items for Special OfferFeature #3: Upselling ProductsFeature #4: Copy Product DataFeature #5: Order Processing MilestonesFeature #6: Products Frequently Viewed TogetherFeature #7: Optimize Delivery CostFeature #8: Merge RecommendationsFeature #9: Products in Price RangeFeature #10: Calculate the Total Cost of the Shopping Cart ItemsFeature #11: Ad ServingFeature #12: Warehouse and Drop PointsFeature #13: Time-Based Item Price StoreFeature #14: Find Similar ProductsWhat Did We Learn?DIY: Two SumDIY: Three SumDIY: 3Sum ClosestDIY: Insert, Delete, and GetRandom in O(1)DIY: Insert Delete GetRandom O(1) - Duplicates AllowedDIY: Copy List with Random PointerDIY: Find First and Last Position of an Element in Sorted ArrayDIY: Find All Anagrams in a StringDIY: Random Pick IndexDIY: Continuous Subarray SumDIY: Accounts MergeDIY: Range Sum of BSTDIY: Basic Calculator IIDIY: Basic Calculator IIIDIY: Read N Characters Given Read4 II — Call Multiple TimesDIY: Walls and GatesDIY: Time-Based Key-Value StoreDIY: Intersection of Two Arrays
9.
Zoom
12 Lessons
Get started with developing Zoom features and DIY coding tasks for interview prep.
Project Description for ZoomFeature #1: Display Meeting LobbyFeature #2: Serialize and Deserialize Participant DataFeature #3: Meeting ActivityFeature #4: Validate Sorted Participants DataFeature #5: Auto Rotate in Mobile DevicesWhat Did We Learn?DIY: Binary Search Tree IteratorDIY: Serialize and Deserialize Binary TreeDIY: Jump Game IVDIY: Validate the Binary Search TreeDIY: Rotate Image
10.
Plagiarism Checker
6 Lessons
Go hands-on with building a plagiarism checker, detecting code similarities and subsequences.
11.
Network
27 Lessons
Grasp the fundamentals of network structures, protocols, and efficient algorithms for robust implementations.
Project Description for NetworkFeature #1: Total TimeFeature #2: TTL ExpiryFeature #3: Minimum HopsFeature #4: Maximum RoutersFeature #5: Update VLAN IDFeature #6: Transmission ErrorFeature #7: Divide Files Over the NetworkFeature #8: Maximum Clock SkewFeature #9: Update ConfigurationFeature #10: Minimum VariationFeature #11: Weighted Exponential Back-offFeature #12: Peak Signal StrengthWhat Did We Learn?DIY: Time Needed to Inform All EmployeesDIY: All Nodes Distance K in Binary TreeDIY: Jump Game IIDIY: Longest Increasing Path in a MatrixDIY: Flood FillDIY: Valid Palindrome IIDIY: Partition LabelsDIY: Maximum Difference Between Node and AncestorDIY: Rotting OrangesDIY: Longest Subarray With Absolute Diff Less Than Equal to LimitDIY: Add Two NumbersDIY: Add Two Numbers IIDIY: Find Peak Element
12.
Cyber Security
12 Lessons
Take a closer look at developing encryption schemes, verifying integrity, and solving cyber security problems.
Project Description for Cyber SecurityFeature #1: Validate Packet StructureFeature #2: Verify Message IntegrityFeature #3: Find DictionaryFeature #4: Ways to Decode MessageFeature #5: Eligible CandidatesWhat Did We Learn?DIY: UTF-8 ValidationDIY: Verifying an Alien DictionaryDIY: Alien DictionaryDIY: Decode WaysDIY: Find K Closest Elements
13.
Operating System
35 Lessons
Focus on OS concepts like process scheduling, memory management, file handling, and system recovery.
Project Description for Operating SystemFeature #1: Allocate SpaceFeature #2: Resume ProcessFeature #3: Schedule ProcessesFeature #4: Compress FileFeature #5: Recover FilesFeature #6: File Management SystemFeature #7: Serialize and Deserialize File SystemFeature #8: Compress File IIFeature #9: File SearchFeature #10: Decode a MessageFeature #11: Directory IteratorFeature #12: Priority ValidationFeature #13: Reverse CommandsFeature #14: Releasing Process LockFeature #15: Queue Reconstruction by PriorityWhat Did We Learn?DIY: Subarray Sum Equals KDIY: Missing Element in a Sorted ArrayDIY: Course ScheduleDIY: Course Schedule IIDIY: Sequence ReconstructionDIY: Concatenated WordsDIY: Minimum Remove to Make Valid ParenthesesDIY: Design Add and Search Words Data StructureDIY: Serialize and Deserialize N-ary TreeDIY: String CompressionDIY: Regular Expression MatchingDIY: Wildcard MatchingDIY: 24 GameDIY: Flatten Nested List IteratorDIY: Frog JumpDIY: Queue Reconstruction by HeightDIY: Reverse Words in a StringDIY: Single Element in a Sorted Array
14.
Language Compiler
22 Lessons
Build on enhancing understanding of compiler design and optimization through hands-on features.
Project Description for Language CompilerFeature #1: Remove CommentsFeature #2: Evaluate the Arithmetic ExpressionFeature #3: Loop UnrollingFeature #4: Optimization by ReplacementFeature #5: Compilation Step FailureFeature #6: Most Common TokenFeature #7: Exponentiation for Mobile DevicesFeature #8: Divide in Power Save ModeFeature #9: Validate Program BracketsWhat Did We Learn?DIY: Count a Word in the CommentsDIY: Basic CalculatorDIY: Decoding a StringDIY: Find and Replace in a StringDIY: First Bad VersionDIY: Nested List Weight SumDIY: Most Common WordDIY: Pow(x, n)DIY: Divide Two IntegersDIY: Valid ParenthesesDIY: Valid Parenthesis String
15.
Boggle
6 Lessons
Try out Boggle project development, mastering search algorithms and grid-based word search.
16.
Scrabble 2.0
6 Lessons
Walk through building Scrabble 2.0 with word transformation algorithms and interview problem patterns.
17.
Game
9 Lessons
Go hands-on with game development features and interview-driven problem-solving techniques.
Project Description for GameFeature #1: Hand of StraightsFeature #2: Maximum Points You Can Obtain from CardsFeature #3: Balloon SplashWhat Did We Learn?DIY: Divide Array in Sets of K Consecutive NumbersDIY: Find Maximum Sum from Either End of an ArrayDIY: Remove All Adjacent Duplicates In StringDIY: Remove All Adjacent Duplicates in String II
18.
Stocks
19 Lessons
Grasp the fundamentals of enhancing stock trading systems with practical solutions and techniques.
Project Description for StocksFeature #1: Validate PriceFeature #2: Settling PeriodFeature #3: Goals FulfilledFeature #4: Milestone ReachedFeature #5: Top BrokersFeature #6: Assign TransactionsFeature #7: Process TransactionsFeature #8: Find IntervalsWhat Did We Learn?DIY: Valid NumberDIY: Task SchedulerDIY: Split Array into Consecutive SubsequencesDIY: Searching a 2D MatrixDIY: Top K Frequent ElementsDIY: Reverse Nodes in k-GroupDIY: Reverse Linked List IIDIY: String to Integer (atoi)DIY: Daily Temperatures
19.
Computational Biology
21 Lessons
Solve problems in computational biology, DNA mutation, virus detection, protein location, and similarity measures.
Project Description for Computational BiologyFeature #1: Mutate DNAFeature #2: Detect VirusFeature #3: Locate ProteinFeature #4: Identifying ProteinsFeature #5: Mutating a VirusFeature #6: Identify a SpeciesFeature #7: Detecting a ProteinFeature #8: Similarity Measure Between DNA SamplesFeature #9: Kth Missing GeneWhat Did We Learn?DIY: String Transforms into Another StringDIY: Longest Substring with At Most K Distinct CharactersDIY: Longest Palindromic SubstringDIY: Valid PalindromeDIY: Next PermutationDIY: Longest Substring without Repeating CharactersDIY: Palindrome PermutationDIY: Palindromic SubstringsDIY: Edit DistanceDIY: Kth Missing Positive Number
20.
Cellular Operator(AT&T)
20 Lessons
Implement algorithms for optimizing cellular networks, including signal strength, coverage areas, and user management.
Project Description for Cellular OperatorFeature #1: Determine LocationFeature #2: Low Coverage AreaFeature #3: Power Up the StationFeature #4: Query Peak UsersFeature #5: Maximum Contiguous AreaFeature #6: Densest DeploymentFeature #7: Maximum UsersFeature #8: Maximum Signal StrengthWhat Did We Learn?DIY: Search a 2D Matrix IIDIY: Largest Rectangle in HistogramDIY: Maximal rectangleDIY: Open LockDIY: Range Sum Query 2D — ImmutableDIY: Minimum Area RectangleDIY: Sliding Window MaximumDIY: Max Area of an IslandDIY: Max Consecutive Ones IIIDIY: Shortest Bridge
21.
17 Lessons
Master the steps to developing Twitter-like features and solving programming challenges for coding interviews.
Project Description for TwitterFeature #1: Add LikesFeature #2: Merge Tweets In Twitter FeedFeature #3: Identify Peak Interaction TimesFeature #4: Split Users into Two GroupsFeature #5: Drawing a Global Profile of Viral TweetsFeature #6: Incoming Tweets PredictorFeature #7: Trending HashtagsWhat Did We Learn?DIY: Add BinaryDIY: Multiply StringsDIY: Merge Sorted ArraysDIY: Maximum Sum of Three Non-Overlapping ArraysDIY: Is Graph Bipartite?DIY: The Skyline ProblemDIY: Moving Average from a Data StreamDIY: Find Duplicate Files in System
22.
Trees
8 Lessons
Learn how to use various techniques to manipulate and traverse binary trees effectively.
23.
Miscellaneous
14 Lessons
Walk through diverse real-world coding challenges and their optimal algorithmic solutions.
24.
Conclusion
1 Lessons
Explore career development with additional resources on behavioral interviews and data structures.
Certificate of Completion
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