use std::collections::VecDeque;
use std::collections::HashMap;

fn cycle(i: i32, circle: &mut VecDeque<usize>) {
  if i > 0 {
    let v = circle.pop_back().unwrap_or(0);
    circle.push_front(v);
    cycle(i - 1, circle);
  } else if i < 0 {
    let v = circle.pop_front().unwrap_or(0);
    circle.push_back(v);
    cycle(i + 1, circle);
  }
}

fn main() {
  let players: usize = 413;
  let last_marble_worth: usize = 7108200;
  let mut circle: VecDeque<usize> = VecDeque::new();
  let mut scores = HashMap::new();

  circle.push_back(0);

  for marble_value in 1..last_marble_worth+1 {
    if marble_value % 23 != 0 {
      cycle(2, &mut circle);
      circle.push_back(marble_value);
    } else {
      let player = ((marble_value as i32) - 1) % (players as i32);
      let score = scores.entry(player).or_insert(0);

      cycle(-7, &mut circle);
      *score += marble_value + circle.pop_back().unwrap_or(0);
    }
  }

  println!("{}", scores.values().max().unwrap_or(&0));
}