JavaSTL

The competitive programmer's toolkit for Java in VS Code

Stop rewriting the same algorithms. Start solving problems.

Install · Features · Algorithm Library · Keybindings · Contributing

🧠 What is JavaSTL?

JavaSTL brings STL-style algorithm templates directly into your Java workflow inside VS Code.

Whether you're grinding LeetCode, competing on Codeforces, or prepping for ICPC — JavaSTL lets you insert production-ready, optimized algorithm snippets in seconds through a clean two-level picker menu. Every template shows its time and space complexity right in the picker so you always know what you're inserting.

No more Googling segment trees at 2AM. No more copy-pasting from old submissions. Just press a shortcut and get back to thinking.

✨ Features

⚡ Insert Algorithm — Two-Level Category Picker

Browse 27 algorithms organized by category. Pick a category, pick an algorithm, and the code lands exactly where your cursor is — with a green glow highlight so you know what was just inserted.

Insert Algorithm Demo

🔎 Search All Algorithms Instantly

Don't remember which category Dijkstra lives in? Just hit Search All and type dij — fuzzy search finds it across all 27 templates in milliseconds. Each result shows the category and complexity hint.

🏁 Contest Template Generator

One command. One keystroke. A fully configured Main.java with fast I/O — BufferedReader, StringTokenizer, PrintWriter, and a solve() stub — the exact boilerplate that top competitive programmers use to avoid TLE on I/O-heavy problems.

Contest Template Demo

🎨 Smart Snippet Highlighting

Every inserted snippet glows green and clears the moment you start typing — so you always know exactly what JavaSTL just inserted versus what you wrote.

🛡️ Language Guard

JavaSTL only activates inside .java files. No accidental insertions in Python or JS files.

📚 Algorithm Library

Category	Algorithms	Count
🔍 Binary Search	Lower Bound, Upper Bound, First True, Last True, Binary Search on Answer	5
🌲 Trees	Segment Tree, Lazy Segment Tree, Fenwick Tree (BIT), Sparse Table, LCA (Binary Lifting)	5
🕸️ Graphs	BFS, DFS, Dijkstra, Floyd Warshall, Kruskal (MST), DSU, Topological Sort	7
📊 DP	0-1 Knapsack, LIS, LCS, Digit DP, Bitmask DP	5
🔤 Strings	KMP, Z Algorithm, Rabin-Karp, Trie, Rolling Hash	5

27 algorithms — all with time & space complexity hints, inline comments, and usage notes.

⌨️ Keybindings

Shortcut	Action	Context
`Ctrl+Alt+J` / `Cmd+Alt+J`	Insert Algorithm	Inside a `.java` file
`Ctrl+Alt+N` / `Cmd+Alt+N`	New Contest File	Anywhere
`Ctrl+Shift+P` → `JavaSTL`	All commands	Anywhere

Following extension guidelines

Ensure that you've read through the extensions guidelines and follow the best practices for creating your extension.

Extension Guidelines

Working with Markdown

You can author your README using Visual Studio Code. Here are some useful editor keyboard shortcuts:

Split the editor (Cmd+\ on macOS or Ctrl+\ on Windows and Linux).
Toggle preview (Shift+Cmd+V on macOS or Shift+Ctrl+V on Windows and Linux).
Press Ctrl+Space (Windows, Linux, macOS) to see a list of Markdown snippets.

For more information

Enjoy!

Sarthak Bhushan