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✨Getting Started
Course Overview
Who Should Take This Course?
Netflix
Project Description For Netflix
Feature #1: Group Similar Titles
Feature #2: Fetch Top Movies
Feature #3: Find Median Age
Feature #4: Popularity Analysis
Feature #5: Fetch Most Recently Watched Titles
Feature #6: Fetch Most Frequently Watched Titles
Feature #7: Browse Ratings
Feature #8: Verify User Session
Feature #9: Movie Combinations of a Genre
Feature #10: Calculate Median of Buffering Events
Feature #11: Generate Movie Viewing Orders
Feature #12: Maintain Continue Watching Bar
What Did We Learn?
DIY: Group Anagrams
DIY: Merge K Sorted Lists
DIY: Find Median from a Data Stream
DIY: Monotonic Array
DIY: LRU Cache
DIY: LFU Cache
DIY: Min Stack
DIY: Validate Stack Sequences
DIY: Letter Combinations of a Phone Number
DIY: Sliding Window Median
DIY: Permutations
DIY: Maximum Frequency Stack
Facebook
Project Description for Facebook
Feature #1: Friend Circles
Feature #2: Copy Connections
Feature #3: Find Story ID
Feature #4: Request Limiter
Feature #5: Flag Words
Feature #6: Combine Similar Messages
Feature #7: Divide Posts
Feature #8: Overlapping Topics
Feature #9: Recreating the Decision Tree
What Did We Learn?
DIY: Number of Islands
DIY: Number of Provinces
DIY: Number of Connected Components in an Undirected Graph
DIY: Clone Undirected Graph
DIY: Search in Rotated Sorted Array
DIY: Logger Rate Limiter
DIY: Expressive words
DIY: Group Shifted Strings
DIY: Divide Chocolate
DIY: Minimum Window Substring
DIY: Construct a Binary Tree from Preorder and Inorder Traversal
Search Engine
Project Description for Search Engine
Feature #1: Store and Fetch Words
Feature #2: Design Search Autocomplete System
Feature #3: Add White Spaces to Create Words
Feature #4: Suggest Possible Queries After Adding White Spaces
Feature #5: Calculate the Search Ranking Factor
Feature #6: Reorganizing Search Results
Feature #7: Find Searching Time
Feature #8: Distributed Process Coordinator
Feature #9: Finding Minimum Servers
What Did We Learn?
DIY: Implement Trie
DIY: Suggest Relevant Sentences
DIY: Word Break
DIY: Word Break II
DIY: Product of Array Elements Except Itself
DIY: Reorganizing a String
DIY: Exclusive Time of Functions
DIY: Snapshot Array
DIY: Coin Change
DIY: Coin Change 2
DIY: Combination Sum
Google Calendar
Project Description for Google Calendar
Feature #1: Find Meeting Rooms
Feature #2: Show Busy Schedule
Feature #3: Check if Meeting is Possible
Feature #4: Schedule a New Meeting
Feature #5: Find Common Meeting Times
Feature #6: Find Two Sets of Consecutive Days
Feature #7: Longest Busy Period
What Did We Learn?
DIY: Find Interval Sets
DIY: Merge Intervals
DIY: My Calendar
DIY: Insert Interval
DIY: Interval Lists Intersection
DIY: Employee Free Time
DIY: Find Two Non-Overlapping Subarrays Each with Target Sum
DIY: Longest Consecutive Sequence
Stock Scraper
Project Description for Stock Scraper
Feature #1: Traversing DOM Tree
Feature #2: Locating Stock Data
Feature #3: Traversing DOM Tree II
Feature #4: Maximum Profit
What Did We Learn?
DIY: Binary Tree Level Order Traversal
DIY: Lowest Common Ancestor of a Binary Tree
DIY: Lowest Common Ancestor of a Binary Tree III
DIY: Populating Next Right Pointers in Each Node
DIY: Populating Next Right Pointers in Each Node II
DIY: Maximum Subarray
DIY: Best Time to Buy and Sell Stock
UBER
Project Description for Uber
Feature #1: Select Closest Drivers
Feature #2: Path Cost
Feature #3: Plot and Select Path
Feature #4: Fare in Words
Feature #5: Uber Pool
Feature #6: Longest Route
Feature #7: Highest Rank
Feature #8: Optimal Path
What Did We Learn?
DIY: K Closest Points to Origin
DIY: Trapping Rainwater
DIY: Evaluate Division
DIY: Integer to English Words
DIY: Random Pick with Weight
DIY: Diameter of Binary Tree
DIY: Kth Largest Element in an Array
DIY: Minimum Path Sum
Amazon
Project Description for Amazon
Feature #1: Suggest Items for Free Delivery
Feature #2: Suggest Items for Special Offer
Feature #3: Upselling Products
Feature #4: Copy Product Data
Feature #5: Order Processing Milestones
Feature #6: Products Frequently Viewed Together
Feature #7: Optimize Delivery Cost
Feature #8: Merge Recommendations
Feature #9: Products in Price Range
Feature #10: Calculate the Total Cost of the Shopping Cart Items
Feature #11: Ad Serving
Feature #12: Warehouse and Drop Points
Feature #13: Time-Based Item Price Store
Feature #14: Find Similar Products
What Did We Learn?
DIY: Two Sum
DIY: Three Sum
DIY: 3Sum Closest
DIY: Insert, Delete, and GetRandom in O(1)
DIY: Insert Delete GetRandom O(1) - Duplicates Allowed
DIY: Copy List with Random Pointer
DIY: Find First and Last Position of an Element in Sorted Array
DIY: Find All Anagrams in a String
DIY: Random Pick Index
DIY: Continuous Subarray Sum
DIY: Accounts Merge
DIY: Range Sum of BST
DIY: Basic Calculator II
DIY: Basic Calculator III
DIY: Read N Characters Given Read4 II — Call Multiple Times
DIY: Walls and Gates
DIY: Time-Based Key-Value Store
DIY: Intersection of Two Arrays
Zoom
Project Description for Zoom
Feature #1: Display Meeting Lobby
Feature #2: Serialize and Deserialize Participant Data
Feature #3: Meeting Activity
Feature #4: Validate Sorted Participants Data
Feature #5: Auto Rotate in Mobile Devices
What Did We Learn?
DIY: Binary Search Tree Iterator
DIY: Serialize and Deserialize Binary Tree
DIY: Jump Game IV
DIY: Validate the Binary Search Tree
DIY: Rotate Image
Plagiarism Checker
Project Description for Plagiarism Checker
Feature #1: Possible Matches
Feature #2: Return Match
What Did We Learn?
DIY: Number of Matching Subsequences
DIY: Minimum Window Subsequence
Network
Project Description for Network
Feature #1: Total Time
Feature #2: TTL Expiry
Feature #3: Minimum Hops
Feature #4: Maximum Routers
Feature #5: Update VLAN ID
Feature #6: Transmission Error
Feature #7: Divide Files Over the Network
Feature #8: Maximum Clock Skew
Feature #9: Update Configuration
Feature #10: Minimum Variation
Feature #11: Weighted Exponential Back-off
Feature #12: Peak Signal Strength
What Did We Learn?
DIY: Time Needed to Inform All Employees
DIY: All Nodes Distance K in Binary Tree
DIY: Jump Game II
DIY: Longest Increasing Path in a Matrix
DIY: Flood Fill
DIY: Valid Palindrome II
DIY: Partition Labels
DIY: Maximum Difference Between Node and Ancestor
DIY: Rotting Oranges
DIY: Longest Subarray With Absolute Diff Less Than Equal to Limit
DIY: Add Two Numbers
DIY: Add Two Numbers II
DIY: Find Peak Element
Cyber Security
Project Description for Cyber Security
Feature #1: Validate Packet Structure
Feature #2: Verify Message Integrity
Feature #3: Find Dictionary
Feature #4: Ways to Decode Message
Feature #5: Eligible Candidates
What Did We Learn?
DIY: UTF-8 Validation
DIY: Verifying an Alien Dictionary
DIY: Alien Dictionary
DIY: Decode Ways
DIY: Find K Closest Elements
Operating System
Project Description for Operating System
Feature #1: Allocate Space
Feature #2: Resume Process
Feature #3: Schedule Processes
Feature #4: Compress File
Feature #5: Recover Files
Feature #6: File Management System
Feature #7: Serialize and Deserialize File System
Feature #8: Compress File II
Feature #9: File Search
Feature #10: Decode a Message
Feature #11: Directory Iterator
Feature #12: Priority Validation
Feature #13: Reverse Commands
Feature #14: Releasing Process Lock
Feature #15: Queue Reconstruction by Priority
What Did We Learn?
DIY: Subarray Sum Equals K
DIY: Missing Element in a Sorted Array
DIY: Course Schedule
DIY: Course Schedule II
DIY: Sequence Reconstruction
DIY: Concatenated Words
DIY: Minimum Remove to Make Valid Parentheses
DIY: Design Add and Search Words Data Structure
DIY: Serialize and Deserialize N-ary Tree
DIY: String Compression
DIY: Regular Expression Matching
DIY: Wildcard Matching
DIY: 24 Game
DIY: Flatten Nested List Iterator
DIY: Frog Jump
DIY: Queue Reconstruction by Height
DIY: Reverse Words in a String
DIY: Single Element in a Sorted Array
Language Compiler
Project Description for Language Compiler
Feature #1: Remove Comments
Feature #2: Evaluate the Arithmetic Expression
Feature #3: Loop Unrolling
Feature #4: Optimization by Replacement
Feature #5: Compilation Step Failure
Feature #6: Most Common Token
Feature #7: Exponentiation for Mobile Devices
Feature #8: Divide in Power Save Mode
Feature #9: Validate Program Brackets
What Did We Learn?
DIY: Count a Word in the Comments
DIY: Basic Calculator
DIY: Decoding a String
DIY: Find and Replace in a String
DIY: First Bad Version
DIY: Nested List Weight Sum
DIY: Most Common Word
DIY: Pow(x, n)
DIY: Divide Two Integers
DIY: Valid Parentheses
DIY: Valid Parenthesis String
Boggle
Project Description for Boggle
Feature #1: Search for a Single Word in the Boggle Grid
Feature #2: Search for Maximum Number of Words in the Boggle Grid
What Did We Learn?
DIY: Word Search I
DIY: Word Search II
Scrabble 2.0
Project Description for Scrabble
Feature #1: Minimum Moves
Feature #2: Possible Results
What Did We Learn?
DIY: Word Ladder I
DIY: Word Ladder II
Game
Project Description for Game
Feature #1: Hand of Straights
Feature #2: Maximum Points You Can Obtain from Cards
Feature #3: Balloon Splash
What Did We Learn?
DIY: Divide Array in Sets of K Consecutive Numbers
DIY: Find Maximum Sum from Either End of an Array
DIY: Remove All Adjacent Duplicates In String
DIY: Remove All Adjacent Duplicates in String II
Stocks
Project Description for Stocks
Feature #1: Validate Price
Feature #2: Settling Period
Feature #3: Goals Fulfilled
Feature #4: Milestone Reached
Feature #5: Top Brokers
Feature #6: Assign Transactions
Feature #7: Process Transactions
Feature #8: Find Intervals
What Did We Learn?
DIY: Valid Number
DIY: Task Scheduler
DIY: Split Array into Consecutive Subsequences
DIY: Searching a 2D Matrix
DIY: Top K Frequent Elements
DIY: Reverse Nodes in k-Group
DIY: Reverse Linked List II
DIY: String to Integer (atoi)
DIY: Daily Temperatures
Computational Biology
Project Description for Computational Biology
Feature #1: Mutate DNA
Feature #2: Detect Virus
Feature #3: Locate Protein
Feature #4: Identifying Proteins
Feature #5: Mutating a Virus
Feature #6: Identify a Species
Feature #7: Detecting a Protein
Feature #8: Similarity Measure Between DNA Samples
Feature #9: Kth Missing Gene
What Did We Learn?
DIY: String Transforms into Another String
DIY: Longest Substring with At Most K Distinct Characters
DIY: Longest Palindromic Substring
DIY: Valid Palindrome
DIY: Next Permutation
DIY: Longest Substring without Repeating Characters
DIY: Palindrome Permutation
DIY: Palindromic Substrings
DIY: Edit Distance
DIY: Kth Missing Positive Number
Cellular Operator(AT&T)
Project Description for Cellular Operator
Feature #1: Determine Location
Feature #2: Low Coverage Area
Feature #3: Power Up the Station
Feature #4: Query Peak Users
Feature #5: Densest Deployment
Feature #6: Maximum Users
Feature #7: Maximum Contiguous Area
Feature #8: Maximum Signal Strength
What Did We Learn?
DIY: Search a 2D Matrix II
DIY: Largest Rectangle in Histogram
DIY: Maximal Rectangle
DIY: Open Lock
DIY: Range Sum Query 2D — Immutable
DIY: Minimum Area Rectangle
DIY: Sliding Window Maximum
DIY: Max Area of an Island
DIY: Max Consecutive Ones III
DIY: Shortest Bridge
Twitter
Project Description for Twitter
Feature #1: Add Likes
Feature #2: Merge Tweets In Twitter Feed
Feature #3: Identify Peak Interaction Times
Feature #4: Split Users into Two Groups
Feature #5: Drawing a Global Profile of Viral Tweets
Feature #6: Incoming Tweets Predictor
Feature #7: Trending Hashtags
What Did We Learn?
DIY: Add Binary
DIY: Multiply Strings
DIY: Merge Sorted Arrays
DIY: Maximum Sum of Three Non-Overlapping Arrays
DIY: Is Graph Bipartite?
DIY: The Skyline Problem
DIY: Moving Average from a Data Stream
DIY: Find Duplicate Files in System
Trees
Invert Binary Tree
Flip Equivalent Binary Trees
Binary Tree Maximum Path Sum
Binary Tree Zigzag Level Order Traversal
Binary Tree Right Side View
Binary Tree Vertical Order Traversal
Boundary of Binary Tree
Flatten Binary Tree to Linked List
Miscellaneous
Minimum Knight Moves
Sparse Matrix Multiplication
Design In-Memory File System
Spiral Matrix
Design Tic-Tac-Toe
The Maze
Restore IP Addresses
Reconstruct Itinerary
Text Justification
Gas Station
Strong Password Checker
Sudoku Solver
Pacific Atlantic Water Flow
Angle Between the Hands of a Clock
Conclusion
Where to Go from Here?
Practice Mock Interview
Decode the Coding Interview in Go: Real-World Examples
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DIY: Valid Palindrome
DIY: Valid Palindrome
Solve the interview question "Valid Palindrome" in this lesson.
We'll cover the following...
Problem statement
Input
Output
Coding exercise
Problem statement
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