Top 20 C Algorithm Projects

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1. tbox

   1 6 5,112 9.0 C

   🎁 A glib-like multi-platform c library

   

2. SaaSHub

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3. Klib

   2 24 4,677 2.6 C

   A standalone and lightweight C library

   

   Project mention: It's Alive! statgrab Returns After 20 Years | dev.to | 2026-04-28

   I shipped a 1.0.0 modernization this week. Rebuilt the storage on top of klib khash, got it green on PHP 7.4 through 8.5 NTS and ZTS, added a proper OO surface (LcHash with $obj[$key] dimension access), wrote a benchmark script and let it run.

4. sc

   3 17 2,557 3.1 C

   Common libraries and data structures for C.

   

5. quadsort

   4 9 2,205 3.3 C

   Quadsort is a branchless stable adaptive mergesort faster than quicksort.

   

6. earcut.hpp

   5 3 992 6.4 C

   Fast, header-only polygon triangulation

   

   Project mention: Earcut64: Zero-Allocation Triangulation for Tiny Polygons | dev.to | 2025-06-16

   Earcut is almost a teaching example: pick any non-self-intersecting polygon, find an "ear" (three consecutive vertices that form an empty inner triangle), cut it off, repeat. Simple? Yes. Slow? Sometimes. But on contours with few points Earcut can be the fastest tool in the shed, as my benchmarks against iTriangle and Mapbox implementations have shown.

7. blitsort

   6 15 715 3.5 C

   Blitsort is an in-place stable adaptive rotate mergesort / quicksort.

   

8. scrypt

   7 15 515 3.6 C

   The scrypt key derivation function was originally developed for use in the Tarsnap online backup system and is designed to be far more secure against hardware brute-force attacks than alternative functions such as PBKDF2 or bcrypt.

   

9. fastrange

   8 2 318 1.8 C

   A fast alternative to the modulo reduction

   

10. sha-2

    9 1 200 2.4 C

    SHA-2 algorithm implementations (by amosnier)

    

11. cgranges

    10 1 170 2.4 C

    A C/C++ library for fast interval overlap queries (with a "bedtools coverage" example)

    

12. fast_zlib

    11 1 145 0.0 C

    Heavily optimized zlib compression algorithm

    

13. dslib

    12 4 131 2.4 C

    :herb: A library of "connected" data structures

    

14. utf8

    13 1 85 2.3 C

    Fast UTF-8 validation with range algorithm (NEON+SSE4+AVX2) (by cyb70289)

    

15. rhsort

    14 6 78 2.8 C

    Robin Hood Sort, for uniform data

    

16. air-ctl

    15 1 35 0.0 C

    C Language Template Library C语言 模板库

    

17. Veracrypt-Password-Extractor

    16 0 15 - C

    A proof-of-concept DLL that prints out the password a user enters into Veracrypt while decrypting a volume.

    

18. libaca

    17 3 11 2.0 C

    C Library of Aho-Corasick Algorithm based on Coordinate Hash Trie

    

19. arduino-gas-index-algorithm

    18 1 11 3.1 C

    Arduino Library for Sensirion's Gas Index Algorithm, providing a VOC and NOx Index output signal calculated from the SGP40/41 raw signals

    

20. PoxHash

    19 12 8 7.6 C

    A block hashing algorithm with implementations in C, Rust, Go, Nim, Python and JS

    

21. HSL

    20 2 3 4.3 C

    HSL to RGB and RGB to HSL

    

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• [Offer] I am a systems, network, and SciComp programmer, I am looking for small, short gigs to fund my libre projects. I have a good portfolio, and I have adequate grasp of theory. My prices begin at $5 and end at $60 for small, one-time gigs. C, x86-64|Aarch64 Assembly, Go, Python, Shell Scripting

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  www.saashub.com | 13 Jun 2026

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