day9_part2.jakt

/// Expect:
/// - output: "3516007333\n"

import reader
import utility

class Marble {
    public previous: Marble?
    public next: Marble?
    public value: i64
}

function add_marble(mut current: Marble, value: i64) throws -> Marble {
    for i in 0..2 {
        current = current.next!
    }

    let new_marble = Marble(
        previous: current.previous
        next: current
        value
    )

    current.previous!.next = new_marble
    current.previous = new_marble

    return new_marble
}

function player_score(mut current: Marble) throws -> (Marble, i64) {
    for i in 0..7 {
        current = current.previous!
    }

    let score = current.value

    current.previous!.next = current.next
    current.next!.previous = current.previous

    return (current.next!, score)
}

function main() {
    let values = reader::lines_string(day: 9)[0].split(' ')

    let players = values[0].to_int()! as! usize
    let marbles = values[6].to_int()! as! i64 * 100

    mut player_scores: [usize:i64] = [:]

    mut current = Marble(
        previous: None,
        next: None
        value: 1
    )

    current.previous = current
    current.next = current

    mut current_player = 2uz

    for marble in 1..(marbles + 1) {
        if marble % 23 == 0 {
            let update = player_score(current)

            current = update.0

            if not player_scores.contains(current_player) {
                player_scores[current_player] = 0
            }

            player_scores[current_player] += update.1 + marble
        } else {
            current = add_marble(current, value: marble)
        }

        current_player = (current_player + 1) % (players + 1)
        if current_player == 0 {
            current_player++
        }
    }

    mut high_score_player = 0uz
    mut high_score = 0

    for (player, score) in player_scores.iterator() {
        if score > high_score {
            high_score = score
            high_score_player = player
        }
    }

    println("{}", high_score)
}