fn main() {
    fn longer<'a>(a: &'a str, b: &'a str) -> &'a str { if a.len() >= b.len() { a } else { b } }
    let first = String::from("north");
    let second = String::from("west");
    let chosen = longer(&first, &second);
    assert_eq!(chosen, "north");
    println!("Borrowed choice: {chosen}");
}