diff --git a/day-13/Cargo.lock b/day-13/Cargo.lock
deleted file mode 100644
index d0515ae..0000000
--- a/day-13/Cargo.lock
+++ /dev/null
@@ -1,78 +0,0 @@
-# This file is automatically @generated by Cargo.
-# It is not intended for manual editing.
-[[package]]
-name = "day-13"
-version = "0.1.0"
-dependencies = [
- "indoc",
-]
-
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-dependencies = [
- "indoc-impl",
- "proc-macro-hack",
-]
-
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-dependencies = [
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- "quote",
- "syn",
- "unindent",
-]
-
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diff --git a/day-13/Cargo.toml b/day-13/Cargo.toml
deleted file mode 100644
index a4e1f5b..0000000
--- a/day-13/Cargo.toml
+++ /dev/null
@@ -1,10 +0,0 @@
-[package]
-name = "day-13"
-version = "0.1.0"
-authors = ["Tristan Daniël Maat <tm@tlater.net>"]
-edition = "2018"
-
-# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
-
-[dependencies]
-indoc = "0.3"
diff --git a/day-13/input b/day-13/input
deleted file mode 100644
index e614056..0000000
--- a/day-13/input
+++ /dev/null
@@ -1,2 +0,0 @@
-1000391
-19,x,x,x,x,x,x,x,x,x,x,x,x,37,x,x,x,x,x,383,x,x,x,x,x,x,x,23,x,x,x,x,13,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,29,x,457,x,x,x,x,x,x,x,x,x,41,x,x,x,x,x,x,17
diff --git a/day-13/src/main.rs b/day-13/src/main.rs
deleted file mode 100644
index be4bd15..0000000
--- a/day-13/src/main.rs
+++ /dev/null
@@ -1,172 +0,0 @@
-use std::fs;
-
-fn main() -> Result<(), Box<dyn std::error::Error>> {
- let input = fs::read_to_string("input")?;
- let (time, ids) = parse_notes(&input)?;
-
- // Part 1
- let (earliest, arrival) = find_closest_bus(time, &ids);
- println!("{}", (arrival - time) * earliest);
-
- // Part 2
- let timestamp = find_gauss(&ids);
- println!("{}", timestamp);
-
- Ok(())
-}
-
-fn parse_notes(input: &str) -> Result<(u32, Vec<u32>), &str> {
- let mut lines = input.lines();
-
- let estimate = lines
- .next()
- .ok_or("Input too short")?
- .parse()
- .map_err(|_| "Estimate is not a number")?;
-
- let ids = lines
- .next()
- .ok_or("Input too short")?
- .split(',')
- .map(|id| id.parse().unwrap_or(1))
- .collect();
-
- Ok((estimate, ids))
-}
-
-fn find_closest_bus(time: u32, ids: &Vec<u32>) -> (u32, u32) {
- ids.iter()
- .filter(|id| **id != 1)
- .map(|id| {
- let mut arrival = *id;
-
- while arrival < time {
- arrival += id
- }
-
- (*id, arrival)
- })
- .min_by_key(|id| id.1)
- .expect("Must have at least one bus ID")
-}
-
-fn find_gauss(ids: &Vec<u32>) -> u128 {
- let ids: Vec<u128> = ids.iter().map(|id| *id as u128).collect();
- let product: u128 = ids.iter().product();
-
- let gauss = |mut n: u128, mut d: u128, m: u128| -> u128 {
- while d != 1 {
- if m == 1 {
- return 0;
- };
-
- let multiplier = if m > d {
- m / d + (m % d != 0) as u128
- } else {
- 1
- };
-
- n = (n * multiplier) % m;
- d = (d * multiplier) % m;
- }
-
- n / d
- };
-
- (0..ids.len())
- .map(|a| {
- let b = product / ids[a];
- let bi = gauss(1, b, ids[a]);
- let a = (ids[a] * a as u128 - a as u128) % ids[a] as u128;
-
- a * b * bi
- })
- .sum::<u128>()
- % product
-}
-
-#[cfg(test)]
-mod tests {
- use super::*;
- use indoc::indoc;
-
- #[test]
- fn test_simple() -> Result<(), Box<dyn std::error::Error>> {
- let input = indoc!(
- "939
- 7,13,x,x,59,x,31,19
- "
- );
-
- let (time, ids) = parse_notes(input)?;
- let (earliest, arrival) = find_closest_bus(time, &ids);
-
- assert_eq!(arrival, 944);
-
- Ok(())
- }
-
- #[test]
- fn test_simple2() -> Result<(), Box<dyn std::error::Error>> {
- let input = indoc!(
- "939
- 17,x,13,19
- "
- );
-
- let (time, ids) = parse_notes(input)?;
- let timestamp = find_gauss(&ids);
-
- assert_eq!(timestamp, 3417);
-
- Ok(())
- }
-
- #[test]
- fn test_simple3() -> Result<(), Box<dyn std::error::Error>> {
- let input = indoc!(
- "939
- 7,13,x,x,59,x,31,19
- "
- );
-
- let (time, ids) = parse_notes(input)?;
- let timestamp = find_gauss(&ids);
-
- assert_eq!(timestamp, 1068781);
-
- Ok(())
- }
-
- #[test]
- fn test_simple4() -> Result<(), Box<dyn std::error::Error>> {
- let input = indoc!(
- "939
- 67,7,59,61
- "
- );
-
- let (time, ids) = parse_notes(input)?;
- let timestamp = find_gauss(&ids);
-
- assert_eq!(timestamp, 754018);
-
- Ok(())
- }
-
- #[test]
- fn test_simple5() -> Result<(), Box<dyn std::error::Error>> {
- let input = indoc!(
- "939
- 67,x,7,59,61
- "
- );
-
- let (time, ids) = parse_notes(input)?;
- let timestamp = find_gauss(&ids);
-
- assert_eq!(timestamp, 779210);
-
- Ok(())
- }
-}