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//! # Day 13: Knights of the Dinner Table
//!
//! In years past, the holiday feast with your family hasn't gone so well. Not everyone gets along!
//! This year, you resolve, will be different. You're going to find the **optimal seating
//! arrangement** and avoid all those awkward conversations.
//!
//! You start by writing up a list of everyone invited and the amount their happiness would increase
//! or decrease if they were to find themselves sitting next to each other person. You have a
//! circular table that will be just big enough to fit everyone comfortably, and so each person will
//! have exactly two neighbors.
//!
//! For example, suppose you have only four attendees planned, and you calculate their potential
//! happiness as follows:
//!
//! ```txt
//! Alice would gain 54 happiness units by sitting next to Bob.
//! Alice would lose 79 happiness units by sitting next to Carol.
//! Alice would lose 2 happiness units by sitting next to David.
//! Bob would gain 83 happiness units by sitting next to Alice.
//! Bob would lose 7 happiness units by sitting next to Carol.
//! Bob would lose 63 happiness units by sitting next to David.
//! Carol would lose 62 happiness units by sitting next to Alice.
//! Carol would gain 60 happiness units by sitting next to Bob.
//! Carol would gain 55 happiness units by sitting next to David.
//! David would gain 46 happiness units by sitting next to Alice.
//! David would lose 7 happiness units by sitting next to Bob.
//! David would gain 41 happiness units by sitting next to Carol.
//! ```
//!
//! Then, if you seat Alice next to David, Alice would lose `2` happiness units (because David talks
//! so much), but David would gain `46` happiness units (because Alice is such a good listener), for
//! a total change of `44`.
//!
//! If you continue around the table, you could then seat Bob next to Alice (Bob gains `83`, Alice
//! gains `54`). Finally, seat Carol, who sits next to Bob (Carol gains `60`, Bob loses `7`) and
//! David (Carol gains `55`, David gains `41`). The arrangement looks like this:
//!
//! ```txt
//!      +41 +46
//! +55   David    -2
//! Carol       Alice
//! +60    Bob    +54
//!      -7  +83
//! ```
//!
//! After trying every other seating arrangement in this hypothetical scenario, you find that this
//! one is the most optimal, with a total change in happiness of `330`.
//!
//! What is the **total change in happiness** for the optimal seating arrangement of the actual
//! guest list?

use anyhow::Result;

pub const INPUT: &str = include_str!("d13.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() {}
}