Part 2 for 2021 day 4

Dependencies

• [2] P7M5N7HR Part 1 solution for 2021 day 4

Change contents

• replacement in 2021/day4.rs at line 48
  [2.1296]→[2.1296:1388](∅→∅)
  − fn parse_boards<I: Iterator<Item = S>, S: AsRef<str>>(input: &mut I) -> Vec<Vec<Vec<u8>>> {
  [2.1296]

  [2.1388]
  + fn parse_boards<'a, I: Iterator<Item = S>, S: AsRef<str>>(input: &'a mut I) -> impl Iterator<Item=Vec<Vec<u8>>> + 'a {
• edit in 2021/day4.rs at line 63
  [2.1783]→[2.1783:1802](∅→∅)
  − .collect()
• replacement in 2021/day4.rs at line 76
  [2.2204]→[2.2204:2305](∅→∅)
  − let boards = parse_boards(&mut lines.flat_map(Result::ok));

  − let (score,step) = boards.iter()
  [2.2204]

  [2.2305]
  + let mut lines = lines.flat_map(Result::ok);

  + let boards = parse_boards(&mut lines);

  + let (score1,step1,score2,step2) = boards
• replacement in 2021/day4.rs at line 83
  [2.2508]→[2.2508:2729](∅→∅)
  − .min_by(|(_,a),(_,b)| a.cmp(b))

  − .unwrap();

  − println!("Time: {}", step);

  − println!("Score: {}", score);

  − let (last_called,_) = draws.iter()

  − .filter(|(_,w)| *w == &step)

  − .next()
  [2.2508]

  [2.2729]
  + .fold(None, |acc, (score,step)| match acc {

  + None => Some((score,step,score,step)),

  + Some((score1,step1,score2,step2)) => {

  + let (score1,step1) = if step < step1 {

  + (score,step)

  + } else {

  + (score1,step1)

  + };

  + let (score2,step2) = if step > step2 {

  + (score,step)

  + } else {

  + (score2,step2)

  + };

  + Some((score1,step1,score2,step2))

  + }

  + })
• edit in 2021/day4.rs at line 100
  [2.2748]

  [2.2748]
  + println!("- Part 1 -");

  + println!("Time: {}", step1);

  + println!("Score: {}", score1);

  + let (last_called,_) = draws.iter().filter(|(_,step)| **step == step1).next().unwrap();
• replacement in 2021/day4.rs at line 105
  [2.2794]→[2.2794:2872](∅→∅)
  − println!("Product: {}", score * <u8 as Into<usize>>::into(*last_called));
  [2.2794]

  [2.2872]
  + println!("Product: {}", score1 * *last_called as usize);

  + println!();

  + println!("- Part 2 -");

  + println!("Time: {}", step2);

  + println!("Score: {}", score2);

  + let (last_called,_) = draws.iter().filter(|(_,step)| **step == step2).next().unwrap();

  + println!("Last called: {}", last_called);

  + println!("Product: {}", score2 * *last_called as usize);

  +