Interview prep

LeetCode questions

0 / 75 solved

Tech Interviews quick recap

It is kind of Blind 75 and Blind 150, but I might add problems here and there that I feel are must-dos for understanding.

Arrays & Hashing Two Pointers Sliding Window Stack Binary Search Linked List Trees Heap / Priority Queue Backtracking Tries Graphs Advanced Graphs 1-D Dynamic Programming 2-D Dynamic Programming Greedy Intervals Math & Geometry Bit Manipulation

Arrays & Hashing

Contains Duplicate
Valid Anagram
Two Sum
Group Anagrams
Top K Frequent Elements
Product of Array Except Self
Encode and Decode Strings
Longest Consecutive Sequence

Two Pointers

Valid Palindrome
3Sum
Container With Most Water

Sliding Window

Best Time to Buy and Sell Stock
Longest Substring Without Repeating Characters
Longest Repeating Character Replacement
Minimum Window Substring

Stack

Valid Parentheses

Binary Search

Find Minimum in Rotated Sorted Array
Search in Rotated Sorted Array

Linked List

Reverse Linked List
Merge Two Sorted Lists
Reorder List
Remove Nth Node From End of List
Linked List Cycle
Merge k Sorted Lists

Trees

Invert Binary Tree
Maximum Depth of Binary Tree
Same Tree
Subtree of Another Tree
Lowest Common Ancestor of a Binary Search Tree
Validate Binary Search Tree
Construct Binary Tree from Preorder and Inorder Traversal
Binary Tree Level Order Traversal
Kth Smallest Element in a BST
Binary Tree Maximum Path Sum
Serialize and Deserialize Binary Tree

Heap / Priority Queue

Find Median from Data Stream

Backtracking

Combination Sum
Word Search

Tries

Implement Trie (Prefix Tree)
Design Add and Search Words Data Structure
Word Search II

Graphs

Number of Islands
Pacific Atlantic Water Flow
Clone Graph
Course Schedule
Number of Connected Components in an Undirected Graph
Graph Valid Tree

Advanced Graphs

Alien Dictionary

1-D Dynamic Programming

Climbing Stairs
House Robber
House Robber II
Decode Ways
Palindromic Substrings
Longest Palindromic Substring
Coin Change
Word Break
Maximum Product Subarray
Longest Increasing Subsequence

2-D Dynamic Programming

Unique Paths
Longest Common Subsequence

Greedy

Maximum Subarray
Jump Game

Intervals

Insert Interval
Merge Intervals
Non-overlapping Intervals
Meeting Rooms
Meeting Rooms II

Math & Geometry

Rotate Image
Spiral Matrix
Set Matrix Zeroes

Bit Manipulation

Number of 1 Bits
Counting Bits
Reverse Bits
Missing Number
Sum of Two Integers

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Reading Shelf

System design and engineering papers worth reading alongside interview prep.

1. Scaling Architecture & Infrastructure 2. Capacity Estimation & Benchmarks 3. Rate Limiting & Traffic Throttling 4. Distributed Data Hashing & Partitioning 5. Key-Value & Storage Engines 6. Unique ID Generation 7. Web APIs & URL Shorteners 8. Web Crawling & Indexing 9. Notification Systems & Messaging 10. News Feed & Social Graph Systems 11. Real-Time Chat & Communications 12. Search Autocomplete & Stream Processing

1. Scaling Architecture & Infrastructure

Hypertext Transfer Protocol
Should you go Beyond Relational Databases?
Multi-master replication
NDB Cluster Replication: Multi-Master and Circular Replication
Caching Strategies and How to Choose the Right One
Single point of failure
Amazon CloudFront Dynamic Content Delivery
Configure Sticky Sessions for Your Classic Load Balancer
Active-Active for Multi-Regional Resiliency
Amazon EC2 High Memory Instances
What it takes to run Stack Overflow
What The Heck Are You Actually Using NoSQL For

2. Capacity Estimation & Benchmarks

Google Pro Tip: Use Back-Of-The-Envelope-Calculations To Choose The Best Design
System design primer
Latency Numbers Every Programmer Should Know
Amazon Compute Service Level Agreement
Compute Engine Service Level Agreement (SLA)
SLA summary for Azure services

3. Rate Limiting & Traffic Throttling

Rate-limiting strategies and techniques
Twitter rate limits
Google docs usage limits
IBM microservices
Throttle API requests for better throughput
Stripe rate limiters
Shopify REST Admin API rate limits
Better Rate Limiting With Redis Sorted Sets
System Design - Rate limiter and Data modelling
How we built rate limiting capable of scaling to millions of domains
Redis website
Lyft rate limiting
Scaling your API with rate limiters
What is edge computing
Rate Limit Requests with Iptables
OSI model

4. Distributed Data Hashing & Partitioning

Consistent hashing
Consistent Hashing - Tom White
Dynamo: Amazon's Highly Available Key-value Store
Cassandra - A Decentralized Structured Storage System
How Discord Scaled Elixir to 5,000,000 Concurrent Users
CS168: The Modern Algorithmic Toolbox - Consistent Hashing
Maglev: A Fast and Reliable Software Network Load Balancer

5. Key-Value & Storage Engines

Amazon DynamoDB
Memcached
Redis
Dynamo: Amazon’s Highly Available Key-value Store
Apache Cassandra
Bigtable: A Distributed Storage System for Structured Data
Merkle tree
Cassandra architecture
SSTable and Log-Structured Storage
Bloom filter

6. Unique ID Generation

Universally unique identifier
Ticket Servers: Distributed Unique Primary Keys on the Cheap
Announcing Snowflake
Network time protocol

7. Web APIs & URL Shorteners

A RESTful Tutorial
Bloom filter

8. Web Crawling & Indexing

US Library of Congress
EU Web Archive
Digimarc Piracy Intelligence
Web Crawling Survey (Christopher Olston, Marc Najork)
29% Of Sites Face Duplicate Content Issues
Donald J. Patterson, Web Crawling Slides
Google Dynamic Rendering

9. Notification Systems & Messaging

Twilio SMS
Nexmo SMS
SendGrid
Mailchimp
You Cannot Have Exactly-Once Delivery
Security in Push Notifications
RabbitMQ Queued Messages

10. News Feed & Social Graph Systems

How News Feed Works - Facebook
Friend of Friend recommendations with Neo4j and SQL Server

11. Real-Time Chat & Communications

Erlang at Facebook
Messenger and WhatsApp process 60 billion messages a day
Long tail distribution
The Underlying Technology of Messages - Facebook
How Discord Stores Billions of Messages
Apache ZooKeeper
The evolution of WeChat background system
End-to-end encryption - WhatsApp
Flannel: An Application-Level Edge Cache to Make Slack Scale

12. Search Autocomplete & Stream Processing

The Life of a Typeahead Query - Facebook
How We Built Prefixy: A Scalable Prefix Search Service
Prefix Hash Tree: An Indexing Data Structure over Distributed Hash Tables
MongoDB
Unicode Frequently Asked Questions
Apache Hadoop
Spark Streaming
Apache Storm
Apache Kafka Documentation