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//! # Day 21: RPG Simulator 20XX
//!
//! Little Henry Case got a new video game for Christmas. It's an [RPG], and he's stuck on a boss.
//! He needs to know what equipment to buy at the shop. He hands you the [controller].
//!
//! In this game, the player (you) and the enemy (the boss) take turns attacking. The player always
//! goes first. Each attack reduces the opponent's hit points by at least `1`. The first character
//! at or below `0` hit points loses.
//!
//! Damage dealt by an attacker each turn is equal to the attacker's damage score minus the
//! defender's armor score. An attacker always does at least `1` damage. So, if the attacker has a
//! damage score of `8`, and the defender has an armor score of `3`, the defender loses `5` hit
//! points. If the defender had an armor score of `300`, the defender would still lose `1` hit
//! point.
//!
//! Your damage score and armor score both start at zero. They can be increased by buying items in
//! exchange for gold. You start with no items and have as much gold as you need. Your total damage
//! or armor is equal to the sum of those stats from all of your items. You have **100 hit points**.
//!
//! Here is what the item shop is selling:
//!
//! ```txt
//! Weapons:    Cost  Damage  Armor
//! Dagger        8     4       0
//! Shortsword   10     5       0
//! Warhammer    25     6       0
//! Longsword    40     7       0
//! Greataxe     74     8       0
//!
//! Armor:      Cost  Damage  Armor
//! Leather      13     0       1
//! Chainmail    31     0       2
//! Splintmail   53     0       3
//! Bandedmail   75     0       4
//! Platemail   102     0       5
//!
//! Rings:      Cost  Damage  Armor
//! Damage +1    25     1       0
//! Damage +2    50     2       0
//! Damage +3   100     3       0
//! Defense +1   20     0       1
//! Defense +2   40     0       2
//! Defense +3   80     0       3
//! ```
//!
//! You must buy exactly one weapon; no dual-wielding. Armor is optional, but you can't use more
//! than one. You can buy 0-2 rings (at most one for each hand). You must use any items you buy. The
//! shop only has one of each item, so you can't buy, for example, two rings of Damage +3.
//!
//! For example, suppose you have `8` hit points, `5` damage, and `5` armor, and that the boss has
//! `12` hit points, `7` damage, and `2` armor:
//!
//! - The player deals `5-2 = 3` damage; the boss goes down to 9 hit points.
//! - The boss deals `7-5 = 2` damage; the player goes down to 6 hit points.
//! - The player deals `5-2 = 3` damage; the boss goes down to 6 hit points.
//! - The boss deals `7-5 = 2` damage; the player goes down to 4 hit points.
//! - The player deals `5-2 = 3` damage; the boss goes down to 3 hit points.
//! - The boss deals `7-5 = 2` damage; the player goes down to 2 hit points.
//! - The player deals `5-2 = 3` damage; the boss goes down to 0 hit points.
//!
//! In this scenario, the player wins! (Barely.)
//!
//! You have **100 hit points**. The boss's actual stats are in your puzzle input. What is **the
//! least amount of gold you can spend** and still win the fight?
//!
//! [RPG]: https://en.wikipedia.org/wiki/Role-playing_video_game
//! [controller]: https://en.wikipedia.org/wiki/Game_controller

use anyhow::Result;

pub const INPUT: &str = include_str!("d21.txt");

pub fn solve_part_one(input: &str) -> Result<i64> {
    Ok(0)
}

pub fn solve_part_two(input: &str) -> Result<i64> {
    Ok(0)
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn part_one() {}

    #[test]
    fn part_two() {}
}