#![allow(unused_variables)]
fn main() {
    println!("Hello {:5}!", "x");
    println!("Hello {:1$}!", "x", 5);
    println!("Hello {1:0$}!", 5, "x");
    println!("Hello {:width$}!", "x", width = 5);
    let width = 5;
    println!("Hello {:width$}!", "x");
}