This repo aims to be an introduction to simple data structures and algorithms. Users are invited to provide their own implementation of the data structures and validate the implementation through unit testing.

The implementation is provided is Java, but some things are left out:

• Collections don't implement java.util.* interfaces to keep it simple
• eg: iterators are left out, isEmpty(), etc
• Performance is not relevant for naive implementations. If time allows we will delve deep into performance
• Generics are not used to keep it simple
• Ideally, Big-O notation would be inferred through benchmarking but that part isn't implemented yet. PRs welcome

All the tests should pass by running ./gradlew test.

If you want to try your own implementation, run ./gradlew -q removeImpls to delete all code within the org.datastructures.algos.*.impl.* classes. Implement your own and make sure the tests pass.

Check the README.md on each package to see how it is supposed to work.

Open an issue/PR with any kind suggestion or comment and I will look into it. Code, typos, unit tests, spelling, copy or any other suggestions are welcome.

• Lists
  • Linked List
  • Array List
  • Persistent Lists
  • Sorting algorithms
• Sets
• Maps
  • HashMap
    • Chained
    • Open addressing
  • Persistent Maps via HAMTs
• Stack
• Queue
  • Priority Queue
• Tree
  • Binary Tree
  • Red/black, AVL, etc
  • B-Tree
  • Traversal algorithms
• Benchmarks (WIP)