#![allow(dead_code, deprecated, unused_variables, unused_mut)] use std::ops::Div; #[derive(Debug, Eq, PartialEq)] struct Rational { numerator: usize, denominator: usize, } impl Rational { fn new(numerator: usize, denominator: usize) -> Self { if denominator == 0 { panic!("Zero is an invalid denominator!"); } let gcd = gcd(numerator, denominator); Self { numerator: numerator / gcd, denominator: denominator / gcd, } } } impl Div for Rational { type Output = Self; fn div(self, rhs: Self) -> Self::Output { if rhs.numerator == 0 { panic!("Cannot divide by zero-valued `Rational`!"); } let numerator = self.numerator * rhs.denominator; let denominator = self.denominator * rhs.numerator; Self::new(numerator, denominator) } } fn gcd(x: usize, y: usize) -> usize { let mut x = x; let mut y = y; while y != 0 { let t = y; y = x % y; x = t; } x } fn main() { assert_eq!(Rational::new(1, 2), Rational::new(2, 4)); assert_eq!(Rational::new(1, 2) / Rational::new(3, 4), Rational::new(2, 3)); }