CLAUDE.md

1# CLAUDE.md
2 
3This file provides guidance to AI coding assistants (Claude Code, Cursor, OpenCode, etc.) when working with code in this repository.
4 
5## Repository Overview
6 
7This is [doocs/leetcode](https://github.com/doocs/leetcode) — a large collection of LeetCode, Coding Interviews, and other algorithm problem solutions, each implemented in multiple programming languages (Python, Java, C++, Go, TypeScript, Rust, C#, PHP, JavaScript, Kotlin, Swift, Scala, Ruby, Nim, Shell, SQL).
8 
9## Directory Structure
10 
11- **`solution/`** — Main LeetCode solutions, organized by problem number ranges (e.g., `0000-0099/`, `0100-0199/`). Each problem has its own directory (e.g., `0000-0099/0001.Two Sum/`) containing:
12    - `README.md` / `README_EN.md` — Chinese/English problem descriptions
13    - `Solution.{py,java,cpp,go,ts,cs,rs,...}` — Solution files in each language
14    - Follow standard LeetCode class-based structure: `class Solution` with the method
15 
16- **`lcof/`** — 剑指 Offer (Coding Interviews, 2nd Edition) — problem directories named with Chinese titles
17- **`lcof2/`** — 剑指 Offer 专项突击版 (Coding Interviews, Special Edition)
18- **`lcci/`** — 程序员面试金典 (Cracking the Coding Interview, 6th Edition) — `01.01.Is Unique` format
19- **`lcp/`** — LeetCode Contest Problems
20- **`lcs/`** — LeetCode Contest (separate series)
21- **`basic/`** — Basic algorithm implementations (sorting algorithms like BubbleSort, QuickSort, etc.)
22 
23## Development Workflow
24 
25### Adding a New Solution
26 
271. Create a new problem directory under the appropriate parent (e.g., `solution/0000-0099/0042.My Problem/`)
282. Add `Solution.py`, `Solution.java`, `Solution.cpp`, `Solution.go`, `Solution.ts`, `Solution.rs`, `Solution.cs`, etc.
293. Add `README.md` and `README_EN.md` with problem description and solution explanations
304. Follow the existing templates in `solution/template.md` for README formatting
315. All language solutions must implement the same algorithm logic
32 
33### Code Formatting
34 
35All code must be formatted before committing. The lint-staged hooks run automatically on pre-commit:
36 
37```bash
38# JavaScript/TypeScript/PHP/SQL/Markdown
39npx prettier --write "**/*.{js,ts,php,sql,md}"
40 
41# Python
42py -m black -S <file>
43 
44# C/C++/Java
45npx clang-format -i --style=file <file>
46 
47# Go
48gofmt -w <file>
49 
50# Rust
51rustfmt <file>
52```
53 
54Or run the full formatting script:
55 
56```bash
57python run_format.py
58```
59 
60### Installation
61 
62```bash
63npm install        # Installs dev dependencies and triggers pip install for Python deps
64```
65 
66### CI/CD
67 
68GitHub Actions automatically run:
69 
70- **clang-format** lint on C/C++/Java files
71- **Black** lint on Python files
72- **Prettier** on JS/TS/PHP/SQL/Markdown files
73- **Deploy** workflow for the documentation site
74 
75## Solution Patterns
76 
77- Python solutions use `List` from typing (imported implicitly by LeetCode environment)
78- Go solutions include `package main` header (added/removed by formatting script)
79- PHP solutions include `<?php` header (added/removed by formatting script)
80- SQL solutions uppercase built-in function names (handled by `run_format.py`)
81- C# solutions contributed by [@kfstorm](https://github.com/kfstorm)
82 
83## Key Conventions
84 
85- Problem directories follow naming convention: `{NUMBER}.{Problem Name with Spaces}`
86- Each solution file is named `Solution.{ext}` (capital S)
87- README files use special HTML comment markers for templating (e.g., `<!-- problem:start -->`, `<!-- solution:start -->`)
88- Solutions should match the problem's required class/method signature from LeetCode
89