Function advent_solutions::advent2017::day09::part2

pub fn part2(root: &Node) -> usize

Now, you're ready to remove the garbage.

To prove you've removed it, you need to count all of the characters within the garbage. The leading and trailing < and > don't count, nor do any canceled characters or the ! doing the canceling.

• <>, 0 characters.

  let root = Node::from_bytes(b"<>")
      .to_result()
      .unwrap();
  
  assert_eq!(part2(&root), 0);

• <random characters>, 17 characters.

  let root = Node::from_bytes(b"<random characters>")
      .to_result()
      .unwrap();
  
  assert_eq!(part2(&root), 17);

• <<<<>, 3 characters.

  let root = Node::from_bytes(b"<<<<>")
      .to_result()
      .unwrap();
  
  assert_eq!(part2(&root), 3);

• <{!>}>, 2 characters.

  let root = Node::from_bytes(b"<{!>}>")
      .to_result()
      .unwrap();
  
  assert_eq!(part2(&root), 2);

• <!!>, 0 characters.

  let root = Node::from_bytes(b"<!!>")
      .to_result()
      .unwrap();
  
  assert_eq!(part2(&root), 0);

• <!!!>>, 0 characters.

  let root = Node::from_bytes(b"<!!!>>")
      .to_result()
      .unwrap();
  
  assert_eq!(part2(&root), 0);

• <{o"i!a,<{i<a>, 10 characters.

  let root = Node::from_bytes(b"<{o\"i!a,<{i<a>")
      .to_result()
      .unwrap();
  
  assert_eq!(part2(&root), 10);

How many non-canceled characters are within the garbage in your puzzle input?