Pythagorean Theorem

main.rs

use std::fmt::{self, Display};

fn main() {
	let b = None;
	let a = None;
	let c = Some(5.0);
	let ans = pyth(a, b, c).unwrap();

	println!("Answer: {}", ans);
	println!("{:?}", ans);
}

type FLOAT = f32; // Could be f64 for double precision

#[derive(Debug)]
enum Output {
	Integer(u32),
	Float(FLOAT),
}

impl Output {
	fn new(val: FLOAT) -> Self {
		let root = val.sqrt();

		if (root.round() - root).abs() < 1e-4 {
			Output::Integer(root.round() as _)
		} else {
			Output::Float(val)
		}
	}
}

impl Display for Output {
	fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> fmt::Result {
		match self {
			Output::Integer(int) => write!(f, "{}", int),
			Output::Float(float) => write!(f, "√{:.}", float),
		}
	}
}

type IN = Option<FLOAT>;

fn pyth(a: IN, b: IN, c: IN) -> Option<Output> {
	let out = if c.is_none() {
		a?.powi(2) + b?.powi(2)
	} else {
		c?.powi(2) - a.or(b)?.powi(2)
	};

	Some(Output::new(out))
}