# krahets/hello-algo

《Hello 算法》：动画图解、一键运行的数据结构与算法教程。支持简中、繁中、English、日本語，提供 Python, Java, C++, C, C#, JS, Go, Swift, Rust, Ruby, Kotlin, TS, Dart 等代码实现

Repository: https://github.com/krahets/hello-algo
Canonical: https://ross.abutalabs.com/products/hello-algo
Homepage: https://www.hello-algo.com
Language: Java
License: NOASSERTION
License Family: other
Topics: algorithms, data-structures, data-structures-and-algorithms, dsa, leetcode, algo, algorithm, data-structure, book, education, programming
Last push: 2026-08-17T20:58:58+00:00

## Health v2 (maintenance only)
Score: 75/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 98, release rhythm 31, longevity 99
- inputs: {"age_days": 1398, "days_push": 16, "days_rel": 244, "gap_med": 391, "n_releases_24m": 2}
- flags: no_license
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 129622, forks 15522 (observed 2026-08-28T04:12:24.200220+00:00)

## What it is
An open-source, beginner-friendly book teaching data structures and algorithms with animated illustrations and instantly runnable code examples. It is available in multiple languages (Chinese, English, Japanese, Russian) with implementations in 13+ programming languages.

## Use cases
- learn data structures and algorithms from scratch
- prepare for coding interviews and leetcode practice
- see algorithm implementations in my favorite programming language
- find a free alternative to paid DSA textbooks
- understand algorithms visually with animations
- run tutorial code examples locally while learning

## When to choose
- you are a beginner wanting a gentle, visual introduction to DSA
- you want runnable code examples in many languages
- you prefer a free, open-source book with active community support

## When to avoid
- you need an exhaustive advanced algorithms reference (e.g., CLRS-level depth)
- you need a runnable library to import into production code
- you require a formally licensed resource (license is non-standard)

## Facets
- artifact type: learning-resource
- maturity: active
- function: documentation, developer-tools
- domain: education, tutorials, programming-languages
- platform: cross-platform
- tags: data-structures, algorithms, open-source-book, interview-prep, leetcode, multilingual, animations, web

## Member repositories
- krahets/hello-algo (main) score 75

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:12:24.200220+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T16:11:30.905114+00:00, confidence not recorded.
  - readme: https://github.com/krahets/hello-algo (fetched 2026-08-28T04:12:24.200220+00:00, sha 9aa8c73e1eb4)
- Data as of 2026-08-30T08:39:29.467469+00:00.