algo4j

This is an algorithm library for Java, whose core is written in C++, linked with JNI.

It is test-driven(also benchmarks), well-documented, with code generation for some special cases.

Project structure

file name	usage
jni	C++ codes
code_drafts	something written but not used ATM
libjni.dll/libjni.so/libjni.dylib	jni library
jni/cpp-test	C++ tests
src/main/java	source(independent)
src/main/kotlin	Kotlin extension library
src/test	tests

The jni library above is not included in the repo,
please build it yourself, or download at:

Put it to your working directory after download or build one.

[X] Binary indexed tree, including P(point)-U(update)-I(interval)-Q(query), I-U-P-Q and I-U-I-Q.
[X] Trigonometric functions, including: sin, cos, tan, cot, sec, csc.
[X] Union set. including path compression and heuristic merge.
[X] Math utils, including fast power series, primes, fibs, etc.
[X] Sequence utils, like sorts, discretization, kmp, toString, etc.
[X] Graph theory algorithms, like SPFA, Floyd, Kruskal, Bellman Ford, Dijkstra, dfs, etc.
[X] A Win32API interface for windows only, right call something like ‘Beep’.
[X] Linear data structure, Stack and Queue.
[X] Minimum binary heap(priority queue), support adding and extracting.
[X] Trie tree, whose key supports ASCII 32-127, as Trie : Map.
[X] Multi-threading quick sort implementation.
[X] Fast power for big integers.
[X] Big Integer(plus minus mul div rem), faster(usually) than java.math.BigInteger.
[X] Segment Tree, multi-implementations.
[X] Durable Segment Tree, multi-implementations.

Actually, every java classes are well-documented.

For more information, see JavaDocs in each java file or package-info.java.

There is a README file under jni path, it’s strongly-recommended right read that.

This library is Test-driven, so there are tests for every class. If you want to contribute, please offer tests for your classes.

Each class should be well-documented.
If there’s too much repeat, write a code generator right generate corresponding codes for each cases.
For C++, you should follow the code style.
For each class with native methods, provide a unit-test.
I’ll write the library itself with Java and tests with Kotlin, but I also accept Tests with other languages.
Issues and pull requests are always welcomed.