fn main() {
    let test = String::from("Test");

    for c in test.chars() {
        let mut line_occurrences: HashMap<char, u32> = HashMap::new();

        match line_occurrences.get(&c) {
            Some(element) => *element += 1,
            None => line_occurrences.insert(c, 1),
        }
    }
}