struct A {
    a: f32,
    b: f32,
}
impl A {
    fn new(a: f32, b: f32) -> Self {
        A { a, b }
    }
    fn dist(&self, other: &A) -> f32 {
        ((self.a - other.a).powi(2) + (self.b - other.b).powi(2)).sqrt()
    }
}
fn main() {
    let mut v: Vec<A> = Vec::new();
    v.push(A::new(5.0,8.0));
    v.push(A::new(1.0,32.0));
    v.push(A::new(91.0,4.0));
    let dist = v[0].dist(&v[1]);
    println!("{}", dist);
}