Rust

fn main() {
    println!("Hello world");
}

fn main() {
    let s1 = "abcd";
    {
        let s2 = "foo";
        let result = longest(s1, s2);
        println!("result is: {}", result);
    }
}

fn longest<'a>(x: &'a str, y: &'a str) -> &'a str {
    if x.len() > y.len() {
        x
    } else {
        y
    }
}