justHash

justHash is a lightweight, CRT-free, non-cryptographic 64-bit hash algorithm and PRNG (Pseudo-Random Number Generator) written in C++ :)

It is designed as a simple, zero-dependency tool for fast data hashing and random number generation. It can be easily dropped into any project

Features

• CRT-Free: Zero dependencies. Does not rely on std::hash, memcpy, or any other standard library functions.
• 64-bit Optimized: Built on a robust ARX (Add-Rotate-Xor) design with XOR-Folding for superior bit diffusion.
• Irrational Constants: Uses seeds based on the Golden Ratio and Pi to ensure high entropy.
• Header-only: Simply copy the header file into your project to get started.
• PRNG Included: Comes with a fast, high-quality random generator (justRand) based on the same hashing principles.

Usage

Hashing Data

You can compute a hash statically without needing to instantiate an object.

#include "justHash.hpp"
#include <iostream>

int main() {
    const char* data = "bybyby-bebebe";
    unsigned __int64 length = 18;
    unsigned __int64 h = justHash::compute(data, length);

    std::cout << "Hash: 0x" << std::hex << h << std::endl;
    return 0;
}

Random Number Generation

Use the included justRand generator for high-quality pseudo-random numbers.

#include "justHash.hpp"

int main() {
    justRand rng;
    rng.seed(12345);

    unsigned __int64 randomValue = rng.next();
    return 0;
}

Motivation

• I made it just because I needed something for hashing data, so if you want to use it - feel free <3

License

This project is licensed under the MIT License.