GitHub - pertrai1/coding-challenges: Practicing and Learning Solving Code

A personal learning repository for mastering data structures, algorithms, frontend engineering, and system design through hands-on problem solving.

About

Each solution includes complexity analysis, pattern identification, and multiple approaches where applicable. The repository features:

LeetCode problems across easy, medium, and hard difficulty
GreatFrontEnd challenges covering frontend engineering and JS fundamentals
System design problems with full and rapid drill solutions
AI-powered code review via specialized agents (details)
Spaced repetition system with automated review scheduling
Automated quality tooling with ESLint, Prettier, and complexity analysis
Detailed analysis docs with pattern breakdowns and key insights

Quick Stats

Platform	Focus Area	Browse
LeetCode	Data Structures & Algorithms	Solutions
GreatFrontEnd	Frontend Engineering	Solutions
System Design	Architecture & Scalability	Solutions

Other profiles: FrontendMasters | Frontend Mentor | Exercism

Repository Structure

coding-challenges/
├── leetcode/              # LeetCode solutions by difficulty
│   ├── easy/
│   ├── medium/
│   └── hard/
├── greatfrontend/         # GreatFrontEnd solutions
│   ├── gfe-75/            #   GFE 75 curated list
│   └── blind-75/          #   Blind 75 curated list
├── system-design/         # System design practice
│   ├── problems/          #   Problem prompts
│   ├── solutions/         #   Full & rapid drill solutions
│   └── templates/         #   Reusable design templates
├── docs/                  # Documentation & guides
│   ├── analysis/          #   Problem breakdowns
│   ├── techniques/        #   Algorithm pattern guides
│   ├── topics/            #   Topic-specific guides
│   ├── platforms/         #   Platform-specific guides
│   └── interviews/        #   Interview workflow & rubrics
├── interviews/            # Mock interview sessions
└── scripts/               # Quality automation scripts

Each problem directory contains a README.md with the problem description, solution file(s), and test files where applicable.

Browse Solutions

By difficulty: Full Problem Index — all LeetCode problems organized by difficulty and topic.

By platform:

LeetCode Solutions — Platform Guide
GreatFrontEnd Solutions — Platform Guide
System Design Solutions — full and rapid drill formats

By pattern: Two Pointers | Sliding Window | Hash Lookup | All Patterns

Learning Resources

Algorithmic Techniques

Hash Lookup — O(1) lookups with hash tables
Two Pointers — Efficient array traversal
Sliding Window — Subarray/substring problems
Gradient Descent — ML optimization technique

Topic Guides

AI/LLM-Oriented Problems — Algorithms that map to generative AI fundamentals
Math Problems — Number theory and mathematical algorithms

Interview Preparation

Interview Workflow — AI-assisted technical interviews
System Design Templates — Full, rapid, and cheat-sheet templates
Problem-Solving Framework — Polya-inspired quickstart guide

Detailed Analysis

Problem breakdowns in docs/analysis/ covering pattern identification, complexity analysis, key insights, and alternative approaches.

Getting Started

# Clone the repository
git clone https://github.com/pertrai1/coding-challenges.git
cd coding-challenges

# Install dependencies
npm install

# Run tests
npm test

# Run a specific solution
node leetcode/easy/0001-two-sum/two-sum.js

Tools & Quality

Tool	Purpose	Command
Vitest	Test runner	`npm test`
ESLint	Code quality	`npm run lint`
Prettier	Formatting	`npm run format`
Complexity Analyzer	Big O analysis	`npm run complexity:leetcode`

# Quick quality check
npm run quality:check

# Fix all issues
npm run quality:fix

# Comprehensive analysis
npm run quality:full

See Testing Guide and Code Quality Guide for details.

Spaced Repetition

Reviews are automatically scheduled at 1, 3, 7, 14, and 30 days after solving a problem. GitHub issues are created as review reminders. See Interview Workflow for details.

AI Agents

Specialized AI agents assist with code review, test generation, and pattern identification. See AGENTS.md for details.

Contributing

This is a personal learning repository, but suggestions and improvements are welcome. See CLAUDE.md for code review guidelines and quality standards.

License

ISC

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