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use std::{collections::{HashSet, HashMap}};
pub fn run(input: String) {
if !input.is_ascii() {
panic!("input wasn't ascii, character calculations won't work!");
}
let scores_table = make_scores_table();
let ll: Vec<&str> = input.lines().collect();
let score = ll.chunks(3).map(|gm| {
let init: Option<HashSet<char>> = None;
let lb: Vec<char> = gm.into_iter().fold(init, |maybe_acc, m| {
let cs: HashSet<char> = m.chars().collect();
if let Some(acc) = maybe_acc {
let rr: HashSet<char> = acc.intersection(&cs).map(|x| {x.clone()}).collect();
Some(rr)
} else {
Some(cs)
}
})
.expect("didn't get any group members??!")
.into_iter().collect();
let ct = lb.len();
if ct != 1 {
panic!("Couldn't find exactly one badge for group! found {}, {:?}", ct, gm);
}
let ch = lb.into_iter().next().expect("foo");
scores_table.get(&ch).expect(format!("couldn't find score for char {}", ch).as_str())
}).sum::<u32>();
println!("Day 3: {}", score);
}
fn make_scores_table() -> HashMap<char, u32> {
let mut scores_table: HashMap<char,u32> = HashMap::new();
let r1 = 'a'..='z';
for (ix, ch) in r1.enumerate() {
scores_table.insert(ch, (ix as u32)+1);
}
let r2 = 'A'..='Z';
for (ix, ch) in r2.enumerate() {
scores_table.insert(ch, (ix as u32)+27);
}
scores_table
}
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