// #![feature(termination_trait)]

fn main1() -> Option<u32> {
    use std::collections::HashMap;

    let mut scores = HashMap::new();

    scores.insert(String::from("Blue"), 10);
    scores.insert(String::from("Yellow"), 50);

    let team_name = String::from("Blue");
    let score = scores.get(&team_name)?;
    println!("result {}",score);

    Some(1)
}
fn main3() {
    let x = 4;

    //fn equal_to_x(z: i32) -> bool {
    //    z == x
    //}
    let equal_to_x = | z | z == x;

    let y = 4;

    assert!(equal_to_x(y));
}
fn main2() {
    let x = 3 ; // vec![1, 2, 3];

    let equal_to_x = move |z| z == x;

    println!("can't use x here: {:?}", x);

    let y = 3 ; // vec![1, 2, 3];

    assert!(equal_to_x(y));
}

fn main() -> std::io::Result<()> {
    println!("Hello, guessing!");
    main1();
    main2();
    main3();
    Ok(())
}