LeetBox

A leetcode sandbox - Practice algorithm problems using Typescript with quick testing and micro‑benchmarks.

Quick start (CLI)

Prefer the single leetbox command over long npm invocations.

# From the project root
npm install

# Expose the CLI (so you can run `leetbox`)
npm link

# Interactive menu (pick latest / compare / add / remove)
leetbox

# Direct commands (problem name optional; omitting opens a picker)
leetbox latest [problem]
leetbox compare [problem]

# Scaffolding
leetbox add              # interactive add (problem or variant)
leetbox add problem      # create a new problem folder with a naive variant
leetbox add variant      # add a new variant to an existing problem

# Cleanup
leetbox remove           # interactive remove (problem or variant)
leetbox remove problem   # delete an entire problem folder
leetbox remove variant   # delete a variant and unregister it

# Help
leetbox --help

Local dev

Prerequisites: Node 20+ (and dev deps installed locally).

# Install dev deps used by the TypeScript runners
npm i -D tsx typescript @types/node

# Run tests / benchmarks (with or without a problem name)
npm run latest -- binarySearch
npm run compare -- binarySearch

# Omit the name to get an interactive picker
npm run latest
npm run compare

# Code quality (BiomeJS)
npm run lint      # Check for linting issues
npm run format    # Format code
npm run check     # Format + lint + auto-fix
npm run ci        # CI-mode check (no fixes applied)

# Testing
npm test              # Run all tests
npm run test:watch    # Watch mode
npm run test:coverage # Generate coverage report

CI/CD

GitHub Actions workflows are configured for:

• CI (.github/workflows/ci.yml): Runs on push/PR

  • Linting and formatting checks
  • Tests across Node.js 20.x, 22.x
  • Coverage report generation

• Code Quality (.github/workflows/code-quality.yml): Runs on PRs

  • Coverage reports on pull requests
  • TypeScript type checking

• Release (.github/workflows/release.yml): Runs on version tags

  • Triggers on version tags (v*..)
  • Creates GitHub releases with auto-generated notes

• Dependabot (.github/dependabot.yml):

  • Weekly dependency updates
  • GitHub Actions version updates

Project layout

• problems//
  • index.ts: runs tests for the latest implementation of this problem
  • compare.ts: benchmarks all implementations for this problem
  • impl/
    • index.ts: imports variants, exports implementations (array of { name, fn }) and latest, and re‑exports testCases
    • testCases.ts: typed test cases (TestCase<Input, Expected>[])
    • variants/*.ts: each variant exports a <camel>Variant function
• utils/: tiny test runner and benchmark harness
• scripts/: TypeScript CLIs for latest, compare, add, remove (used by leetbox)

Add a new problem

Fastest: use the CLI scaffolder.

# Guided prompts: name + short folder
leetbox add problem

This creates:

• problems//index.ts
• problems//compare.ts
• problems//impl/index.ts
• problems//impl/testCases.ts
• problems//impl/variants/naive.ts

Edit impl/testCases.ts to match the problem. Implement variants/naive.ts, then add more variants as you iterate.

Manual route (if you prefer): mirror the structure above and ensure impl/index.ts exports:

• export const implementations = [{ name, fn }, ...]
• export const latest = implementations[implementations.length - 1]
• export { testCases } from './testCases'

Add or remove a variant

# Add a variant to an existing problem (interactive problem picker)
leetbox add variant

# Remove a variant (also prunes the import and registry entry)
leetbox remove variant

The scaffolder writes impl/variants/<camel>.ts with a <camel>Variant function and appends it to the implementations array so it becomes the new latest.

What’s included

• Test harness: dependency‑free, default deep‑equality via JSON.stringify with an optional custom comparator
• Bench harness: correctness check, warmups, quiet mode, high‑res timing, relative‑to‑best table
• Interactive UX: pick a problem when you omit the name; add/remove problem and variant scaffolding
• Time complexity benchmarks
• Space complexity benchmarks
• TypeScript types for inputs and expected outputs (clean up the any's)
• CI/CD workflows: linting, formatting, tests, coverage, releases

Master the fundamentals

If you are preparing for coding interviews, you should also check out LeetTrivia - an addictive trivia game that helps you master the fundamentals of coding, data structures, algorithms and more.

License

MIT © Vlad Balan