Closed-form expression of Fibonacci numbers

This is done as part of my recreational programming late-night sessions and does not comply with the well-known recursion approach, but instead emphasizes Binet's formula.

Exigent: No language model (so called AI) have been used in this repo. This is all done by me and my perception of Binet's formula, powered with knowladge based on findings on the internet and nothing more. Precision may vary for big numbers. Thats why input is limited to 99.

Build

This repo requires Rust language.
To run the program use Rust's package manager cargo.

• cargo check - This will essentially compile the packages without performing the final step of code generation, which is faster than running cargo build. The compiler will save metadata files to disk so that future runs will reuse them if the source has not been modified. Some diagnostics and errors are only emitted during code generation, so they inherently won’t be reported with cargo check.
• cargo run - Run a binary or example of the local package.

Info

rustc version: rustc 1.98.1 (48a229cea 2026-09-01)
Ref: Wiki
Author: Martin Duchev