5-5.rs

trait Geometry {
    fn area(&self) -> f32;
    fn permeter(&self) -> f32;
}
struct Rectangle {
    width: f32,
    height: f32,
}

impl Geometry for Rectangle {
    fn area(&self) -> f32 {
        self.width * self.height
    }

    fn permeter(&self) -> f32 {
        (self.width * self.height) * 2.0
    }
}

struct Circle {
    radius: f32,
}

impl Geometry for Circle {
    fn area(&self) -> f32 {
        3.14 * self.radius * self.radius
    }

    fn permeter(&self) -> f32 {
        3.14 * 2.0 * self.radius
    }
}

fn main() {
    let rect = Rectangle {
        width: 8.8,
        height: 2.2,
    };

    println!(
        "rect.area:{}, rect.permeter:{}",
        rect.area(),
        rect.permeter()
    );

    let circle = Circle { radius: 10.2 };

    println!(
        "circle.area: {},  circle.permeter:{}",
        circle.area(),
        circle.permeter()
    );
}