day08 part 2

src/main.rs

@@ -1,4 +1,4 @@
 fn main() {
-    aoc_2018::tasks::day08::task1();
+    aoc_2018::tasks::day08::both();
     // aoc_2018::tasks::day08::task2();
 }

src/tasks/day08.rs

@@ -1,14 +1,14 @@
 use crate::utils;
 
-pub fn task1() {
+pub fn both() {
     let input: Vec<usize> = utils::read_file("input/day08.txt")
         .split(" ")
         .map(|x| x.parse().unwrap())
         .collect();
 
-    let (tree, rest) = Node::extract_from(&input);
+    let (tree, _) = Node::extract_from(&input);
     println!("Metadata sum: {}", tree.metadata_sum());
-    println!("rest: {:?}", rest);
+    println!("Task2 sum: {}", tree.task2());
 }
 
 struct Node {
@@ -44,4 +44,18 @@ impl Node {
                 })
                 .sum::<usize>()
     }
+
+    fn task2(&self) -> usize {
+        if self.children.len() > 0 {
+            self.metadata
+                .iter()
+                .map(|meta| match self.children.get(*meta - 1) {
+                    Some(child) => child.task2(),
+                    None => 0,
+                })
+                .sum()
+        } else {
+            self.metadata_sum()
+        }
+    }
 }