use std::collections::{HashSet, VecDeque}; use std::error::Error; use std::io::{self, BufRead}; #[derive(Debug)] struct GameResult { winner: usize, cards: [VecDeque; 2], } fn game_easy(mut cards: [VecDeque; 2]) -> GameResult { loop { let card0 = cards[0].pop_front().unwrap(); let card1 = cards[1].pop_front().unwrap(); if card0 < card1 { cards[1].push_back(card1); cards[1].push_back(card0); } else if card0 > card1 { cards[0].push_back(card0); cards[0].push_back(card1); } else { panic!("cards are equal"); } if cards[0].len() == 0 { return GameResult { winner: 1, cards, } } if cards[1].len() == 0 { return GameResult { winner: 0, cards, } } } } fn game_hard(original_cards: &[VecDeque; 2]) -> GameResult { let mut cards = original_cards.clone(); let mut states = HashSet::new(); loop { if states.contains(&cards[0]) { //println!("loop return from game {}", current_game_count); //result_cache.insert(original_cards.clone(), 0); return GameResult { winner: 0, cards, }; } states.insert(cards[0].clone()); let card0 = cards[0].pop_front().unwrap(); let card1 = cards[1].pop_front().unwrap(); let round_winner = if cards[0].len() >= card0 && cards[1].len() >= card1 { game_hard(&[cards[0].iter().cloned().take(card0).collect(), cards[1].iter().cloned().take(card1).collect()]).winner } else if card0 < card1 { 1 } else if card0 > card1 { 0 } else { panic!("cards are equal"); }; match round_winner { 0 => { cards[0].push_back(card0); cards[0].push_back(card1); }, 1 => { cards[1].push_back(card1); cards[1].push_back(card0); }, _ => panic!("wrong winner value"), } if cards[0].len() == 0 { //println!("winner 1 return from game {}", current_game_count); return GameResult { winner: 1, cards, }; } if cards[1].len() == 0 { //println!("winner 0 return from game {}", current_game_count); return GameResult { winner: 0, cards, }; } } } fn handle_result(game_result: GameResult) { let mut sum = 0; let len = game_result.cards[game_result.winner].len(); for i in 0..len { sum += (len-i) * game_result.cards[game_result.winner][i]; } println!("{:?}", game_result); println!("{}", sum); } fn main() -> Result<(), Box> { let stdin = io::stdin(); let mut cards: [VecDeque; 2] = Default::default(); let mut current_player = usize::MAX; for line_result in stdin.lock().lines() { let line = line_result?; if line.starts_with("Player") { current_player = line.strip_prefix("Player ").unwrap().strip_suffix(":").unwrap().parse::()? - 1; } else if line != "" { cards[current_player].push_back(line.parse()?); } } handle_result(game_easy(cards.clone())); handle_result(game_hard(&cards)); Ok(()) }