Swap 2 fields of a struct rust

swap.rs

#[derive(Debug)]
pub struct Demo {
    f: i32
}

#[derive(Debug)]
pub struct Other {
    a: Demo,
    b: Demo
    
}

impl Other {
    fn swapp(&mut self) {
         std::mem::swap(&mut self.a, &mut self.b);
    }
}
fn main() {
    let mut s = Other{a: Demo{f: 0}, b: Demo{f: 1}};
    println!("{:?}",s);
    s.swapp();
    println!("{:?}",s);
}