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extern crate advent_of_code_2017;
use advent_of_code_2017::*;
extern crate regex;
use regex::Regex;
fn main() {
let args = AdventArgs::init();
let names_re = Regex::new(r"[a-z]+").unwrap();
let weight_re = Regex::new(r"\d+").unwrap();
let tree: Vec<(String, Vec<String>, i32)> = args.input.iter()
.map(|line| {
let mut matches = names_re.find_iter(line);
let base = matches.next().unwrap().as_str().to_string();
let leaves = matches.map(|m| m.as_str().to_string()).collect();
let weight = weight_re.find(line).unwrap().as_str().parse().unwrap();
(base, leaves, weight)
}).collect();
let mut possible_roots: Vec<String> = tree.iter().map(|&(ref id, _, _)| id.clone()).collect();
for &(_, ref leaves, _) in &tree {
for leaf in leaves {
let index = possible_roots.iter().position(|x| x == leaf).unwrap();
possible_roots.remove(index);
}
}
let root = &possible_roots[0];
if args.part == 1 {
println!("{:?}", root);
} else {
find_unweighted_plate(&root, &tree);
}
}
fn find_unweighted_plate(root: &String, tree: &Vec<(String, Vec<String>, i32)>) -> i32 {
let root_node = find_node(&root, &tree);
let &(_, ref leaves, ref weight) = root_node;
let leaf_weights: Vec<i32> = leaves.iter().map(|leaf| {
find_unweighted_plate(&leaf, &tree)
}).collect();
if let Some(base_leaf_weight) = leaf_weights.first() {
if let Some(different_leaf_weight) = leaf_weights.iter().find(|&w| w != base_leaf_weight) {
println!("Unbalanced plate is off by {}", (different_leaf_weight-base_leaf_weight).abs());
println!("Towers on plate: {:?} weigh {:?}", leaves, leaf_weights);
// This still needs some manual work to get to the puzzle
// output. Take the first unbalanced plate, figure out
// which is the unbalanced tower visually, find its
// individual weight in the file, and add/subtract as
// necessary.
}
}
leaf_weights.iter().sum::<i32>() + weight
}
fn find_node<'a>(name: &String, tree: &'a Vec<(String, Vec<String>, i32)>) -> &'a (String, Vec<String>, i32) {
tree.iter().find(|&&(ref id, _, _)| id == name).unwrap()
}
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