Solutions to day 10.

2016/day-10/Cargo.toml

@@ -0,0 +1,7 @@
+[package]
+name = "day-10"
+version = "0.1.0"
+authors = ["Bert Peters <bert.ljpeters@gmail.com>"]
+
+[dependencies]
+regex="^0.1"

2016/day-10/src/main.rs

@@ -0,0 +1,88 @@
+extern crate regex;
+
+use regex::Regex;
+use std::env;
+use std::io::prelude::*;
+use std::fs::File;
+use std::io::BufReader;
+use std::collections::HashMap;
+use std::collections::VecDeque;
+use std::cmp::min;
+use std::cmp::max;
+
+fn give_value(values: &mut HashMap<i32, i32>, todo: &mut VecDeque<(i32, i32, i32)>, bot: i32, value: i32)
+{
+    if values.contains_key(&bot) {
+        let current = values[&bot];
+        values.remove(&bot);
+
+        todo.push_back((bot, value, current))
+    } else {
+        values.insert(bot, value);
+    }
+}
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+    let f = File::open(&args[1]).expect("Could not open file");
+    let reader = BufReader::new(f);
+
+    let input_regex = Regex::new(r"value (\d+) goes to bot (\d+)").unwrap();
+    let action_regex = Regex::new(r"bot (\d+) gives low to (bot|output) (\d+) and high to (bot|output) (\d+)").unwrap();
+
+    let mut bot_values = HashMap::new();
+    let mut bot_actions = HashMap::new();
+    let mut action_queue = VecDeque::new();
+
+    for line in reader.lines() {
+        let contents = line.unwrap();
+        match action_regex.captures(&contents) {
+            Some(caps) => {
+                let bot: i32 = caps[1].parse().unwrap();
+                let t1 = &caps[2] == "bot";
+                let n1: i32 = caps[3].parse().unwrap();
+                let t2 = &caps[4] == "bot";
+                let n2: i32 = caps[5].parse().unwrap();
+
+                bot_actions.insert(bot, (t1, n1, t2, n2));
+            },
+            _ => {
+                let caps = input_regex.captures(&contents).unwrap();
+                let value: i32 = caps[1].parse().unwrap();
+                let bot: i32 = caps[2].parse().unwrap();
+
+                give_value(&mut bot_values, &mut action_queue, bot, value);
+            }
+        }
+    }
+
+    let mut bins = HashMap::new();
+
+    while !action_queue.is_empty() {
+        let (bot, val1, val2) = action_queue.pop_front().unwrap();
+
+        let lo = min(val1, val2);
+        let hi = max(val1, val2);
+
+        if lo == 17 && hi == 61 {
+            println!("Bot {} handling 17 and 61", bot);
+        }
+
+        let (tlo, nlo, thi, nhi) = bot_actions[&bot];
+
+        if tlo {
+            give_value(&mut bot_values, &mut action_queue, nlo, lo);
+        } else {
+            bins.insert(nlo, lo);
+        }
+
+        if thi {
+            give_value(&mut bot_values, &mut action_queue, nhi, hi);
+        } else {
+            bins.insert(nhi, hi);
+        }
+    }
+
+    let product = bins[&0] * bins[&1] * bins[&2];
+    println!("Product: {}", product);
+}