JavaScript - 600+ Problems Solved

Plain docs links

• JavaScript (MDN) docs: https://developer.mozilla.org/en-US/docs/Web/JavaScript
• ECMAScript (spec, ECMA-262) docs: https://www.ecma-international.org/publications-and-standards/standards/ecma-262/

---

A curated collection of concise, well-documented JavaScript solutions and learning exercises spanning foundational to advanced topics. Organized into two focused workspaces:

• js-basic - core language fundamentals and small practice problems (arrays, functions, loops, objects, basics of scope and closure).
• js-advanced - deep dives into language internals, performance-aware patterns, advanced async control, generators, and real-world idioms.

This repository is built to teach, demonstrate engineering judgment, and serve as a showcase for interview preparation or client review.

Highlights

• 600+ small, self-contained examples and practice problems (files are single-concept and runnable).
• Clear, commentary-rich code intended for learning and quick inspection.
• Examples focused on readability, testability, and the trade-offs engineers care about (performance, memory, error handling).

Why this repo is useful to you

• Learners: step through files in js-basic to master fundamentals with runnable examples.
• Intermediate/Senior engineers: explore js-advanced for patterns, performance notes, and interview-ready explanations.
• Hiring managers/clients: fast way to evaluate code clarity, judgement, and breadth of JavaScript expertise.

Quick Start

Prerequisites:

• Node.js (LTS recommended - v16+)

Run any example from the repository root. Example using PowerShell:

cd c:\projects\javascript-600-problems\js-basic
node array.js

cd ..\js-advanced
node some-advanced-file.js

Replace array.js or some-advanced-file.js with any file from the respective directories. Most files print a short demonstration to the console.

Project structure - top-level

• js-basic/ - beginner and intermediate problems; single-concept files ideal for learning and interviews.
• js-advanced/ - advanced examples and deep-dive topics with performance notes and defensive patterns.
• README.md - this file (overview + navigation for clients/contributors).

Explore either folder to see the full list of example files. Filenames are descriptive and use kebab-case for readability.

Showcase examples (recommended to run)

• js-basic/array.js - array basics and common operations
• js-basic/function-return.js - function behavior, return patterns
• js-advanced/async-await.js - advanced async patterns and concurrency control
• js-advanced/event-loop.js - microtask vs macrotask ordering demonstration

Running the above will give a quick feel for the code style and teaching approach.

How this repo is organized (developer contract)

• One concept per file. Files are intentionally small to be readable and runnable.
• Example files either log demonstrative output or export pure functions suitable for unit testing.
• Performance or memory-sensitive examples include short notes about complexity and trade-offs.

Edge cases covered in examples (where relevant): empty inputs, large inputs, error handling, and cancellation/cleanup for async examples.

Contribution Guide

We welcome contributions. To keep the repo high-quality and client-ready, please follow these rules:

1. Keep files focused: one concept per file and use kebab-case filenames (async-concurrency.js).
2. Add a short header comment describing the goal, expected output, and complexity characteristics.
3. Provide a small runnable example (console output) and export pure functions where appropriate for unit testing.
4. Avoid introducing external dependencies for core examples. If a new dependency is necessary, explain the reason in your PR.
5. When demonstrating performance comparisons, include measured results and environment details.

Open a PR with a clear title and description. Small, incremental PRs are preferred.

Tests, CI, and validation (recommended)

This repository keeps examples lightweight by default. I recommend the following steps to add quality gates and client-facing confidence:

1. Add a package.json at the repository root (if missing) and include a test runner such as Jest or Vitest.
2. Export pure functions from example files so unit tests can import them. Place tests in a __tests__/ folder.
3. Add a GitHub Actions workflow that runs tests on PRs and pushes a status badge to this README.md.

If you’d like, I can scaffold:

• A minimal package.json with a test script
• One or two example tests for js-basic and js-advanced
• A CI workflow (GitHub Actions) and status badges

Tell me which scaffold(s) you want and I’ll add them.

Code Style and Quality

• Prefer modern JavaScript: const/let, arrow functions when clearer, and descriptive variable names.
• Keep side effects isolated for easier testing.
• Add short comments for any non-obvious decisions or trade-offs.

License

• This project is licensed under the terms of the MIT License.
• You may replace or update the license as needed for client or proprietary projects.

---

Contact & Maintainer

• Name: Md Abu Kayser - Full-Stack Engineer
• js-problems-project: javascript-600-problems
• Maintainer: md-abu-kayser
• Email: abu.kayser.official@gmail.com
• GitHub: github.com/abu.kayser-official

If you’d like this README tailored for a specific purpose - such as hiring managers, open-source contributors, or client deliverables - feel free to request a custom tone or format.

---

It’s designed to be clean, well-structured, and pleasant to explore - perfect for interviews or professional problems solved.

---

If a client or maintainer wants to discuss improvements, pair on content, or request additional problem sets, please open an issue or reach out via the repo's contact information.

---

Enjoy learning and exploring JavaScript - basic to advanced problems lead to big understanding. Thank you for reviewing this project!

---

Thank you for exploring - basic and advanced, focused exercises are a powerful way to master JavaScript and demonstrate engineering judgment.

---