use std::collections::HashMap;
pub type WordCounts = HashMap<String, u32>;

pub fn count(counts: &mut WordCounts, word: String) {
    add(counts, word, 1);
}

pub fn add(counts: &mut WordCounts, word: String, count: u32) {
    let counter = counts.entry(word).or_insert(0);
    *counter += count;
}

pub fn print(counts: &WordCounts, max: usize) {
    let mut counts: Vec<_> = counts.iter().map(|(w,c)| (c,w)).collect();
    counts.sort();
    for (count, word) in counts.into_iter().rev().take(max) {
        println!("{} {}", count, word);
    }
}