#![allow(dead_code)]
#![allow(unused_variables)]
#![allow(unused_assignments)]

use std::collections::*;

fn do_something(mapping: &HashMap<u64, String>, backup: &str) -> &str {
    for i in 0..3 {
        let maybe_v = mapping.get(&i);
        match maybe_v {
            Some(v) => return &v,
        }
    }

    backup
}

fn main() {
    let mut words = HashMap::new();

    words.insert(4, "four".to_owned());
    words.insert(5, "five".to_owned());

    let second = String::new("nothingelse");

    let res = do_something(&words, &second);

    println!("got {:?}", res);
}