day25 finished

data/day25/example01.txt

@@ -0,0 +1,13 @@
+1=-0-2
+12111
+2=0=
+21
+2=01
+111
+20012
+112
+1=-1=
+1-12
+12
+1=
+122

data/day25/input.txt

@@ -0,0 +1,135 @@
+1--
+1-
+1--02
+1122-=2-==0-0=1-2
+2=1-==-1022=10
+1==-02211022=000
+101==210-21=2
+11010==0==221=0=02
+11=1101020=02-11
+1===
+10-2
+10=02=-=02
+1-1--112-202--0
+11-=-0-002=0112-1
+2--0-2=02=-22
+1001-2
+1=101=2=2102-201--1
+1-2==1100--
+2-01=--=1-11
+101-=0010-210==
+1=-21-022121110
+1==21
+22==1
+2-0-=2=1
+2--0=10-00--2-
+1--1=011-2
+1-100-2
+11-1
+112
+222200110-11110-2=
+1==2-210-1122=-2022
+2==1-20-2-=-21
+21=1-=0=-1-=-=-12
+210---=-1===-===00
+1--21=01-022=2-
+11-=
+21-2
+2-22-0
+1==-
+1-----01
+1-0-21-
+211212-22-12--=2
+1=220=10=20200-0
+21-=11-==20=1
+102-2==2-==-0
+1=0=01-
+22=1--0111
+1-----=1==00===0-
+20==-1-121-
+1=--2--21-202=21
+1-0122=--=
+2==-2--===-=-1=-012
+2220=-00-10-
+1==0=---10212-1-
+1221=-022120
+100112
+2-=0=220-=01-1=12-
+1=00
+2122121=2
+2-==
+12-21===10220
+1=0
+22-1=--01-==0
+1-2-2202=1=02
+11-===21-
+1-22=0102-=-222-1
+1021=0=21=0=11=2-2
+1===2222=0-0=
+20=2-=0=
+1=2==02-1-100200
+1=1211211----
+12=1=1---=20
+2--2=2=1100020200
+1=0-002-11-10----
+1=1=-1=-0
+1-21=1=02=21=20
+1-=0-002-0=--=0=
+20-===-1=
+220021012
+12===1001=--=2=1-
+1=-02
+21
+2=200222122
+1-2=110111=012=1-
+1=02=
+101==1-=1=0001
+1=22--1-021
+120
+201-0211
+1-1012211--2=-1=
+12=10202=20
+11-22=2=2=-0==1=00
+11=-
+12-1--2222
+22
+1120--0==
+10=-0=001-
+1=00200200=
+1-20
+1-0-
+10112-202=-011
+11-2=
+1-=10=1-0=-21==11200
+11
+12-0-=01--12
+1-=1121-=0
+120-21=-1=10121=
+1102-22
+21=
+1==--1==---1-==
+12=0--=2210-1==
+22210=1-=0
+1102-20-1
+1=1=2102
+11--=2==-0
+2=0=1=
+21-0-10=
+12-212-2=-==102--
+1==0100210-=
+12210-0-1
+1=0-2-0=
+10-1=211=1-2=
+201-0--
+1--2=00=-1-211
+121=-22100=210--
+122-0-1-
+2=211
+2=1-=2-2-0001=-1
+1102--11=0=1=10==2
+1==01121-2--0=12
+2=21-20=-0-0
+2-212=21-02=1-2-02
+2=1-0
+10-0-=20
+2=2=201

src/days/day25/mod.rs

@@ -0,0 +1,142 @@
+use super::template::{DayTrait, ResultType};
+use crate::common::file::split_lines;
+use itertools::{unfold, Itertools};
+use std::iter::Sum;
+use std::ops::Add;
+use std::str::FromStr;
+use thiserror::Error;
+
+const DAY_NUMBER: usize = 25;
+
+pub struct Day;
+
+impl DayTrait for Day {
+    fn get_day_number(&self) -> usize {
+        DAY_NUMBER
+    }
+
+    fn part1(&self, lines: &str) -> anyhow::Result<ResultType> {
+        let snafu: Snafu = split_lines(lines)
+            .map(|line| line.parse::<Snafu>())
+            .collect::<Result<Vec<_>, _>>()?
+            .into_iter()
+            .sum();
+        Ok(ResultType::String(snafu.as_str()))
+    }
+
+    fn part2(&self, _lines: &str) -> anyhow::Result<ResultType> {
+        Ok(ResultType::Nothing)
+    }
+}
+
+impl Snafu {
+    pub fn as_str(&self) -> String {
+        let value = self.0;
+        if value == 0 {
+            return String::from("0");
+        }
+
+        unfold(value, |value| {
+            if *value == 0 {
+                return None;
+            }
+            let m = (*value + 2) % 5;
+            *value = (*value + 2 - m) / 5;
+            Some(m)
+        })
+        .map(|digit| "=-012".chars().nth(digit).unwrap())
+        .collect_vec()
+        .iter()
+        .rev()
+        .join("")
+    }
+
+    fn new(value: i64) -> Result<Snafu, SnafuError> {
+        if value >= 0 {
+            Ok(Snafu(value as usize))
+        } else {
+            Err(SnafuError::OnlyNonNegativeSnafus(value))
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Hash)]
+struct Snafu(usize);
+
+impl Add for Snafu {
+    type Output = Snafu;
+
+    fn add(self, rhs: Self) -> Self::Output {
+        Snafu(self.0 + rhs.0)
+    }
+}
+
+impl Sum for Snafu {
+    fn sum<I: Iterator<Item = Self>>(iter: I) -> Self {
+        iter.fold(Snafu(0), Add::add)
+    }
+}
+
+impl FromStr for Snafu {
+    type Err = SnafuError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        Snafu::new(
+            s.chars()
+                .map(|c| {
+                    "=-012"
+                        .chars()
+                        .position(|d| d == c)
+                        .ok_or_else(|| SnafuError::IllegalChar(c))
+                })
+                .fold_ok(0, |acc, next| acc * 5 + (next as i64 - 2))?,
+        )
+    }
+}
+
+#[derive(Debug, Error)]
+enum SnafuError {
+    #[error("Illegal Char: {0}")]
+    IllegalChar(char),
+
+    #[error("Only non negative Snafus exist. Got: {0}")]
+    OnlyNonNegativeSnafus(i64),
+}
+
+#[cfg(test)]
+mod test {
+    use super::*;
+    use crate::common::file::read_string;
+    use anyhow::Result;
+
+    #[test]
+    fn test_part1() -> Result<()> {
+        let day = Day {};
+        let lines = read_string(day.get_day_number(), "example01.txt")?;
+        let expected = ResultType::String(String::from("2=-1=0"));
+        let result = day.part1(&lines)?;
+        assert_eq!(result, expected);
+
+        Ok(())
+    }
+
+    #[test]
+    fn test_part2() -> Result<()> {
+        let day = Day {};
+        let lines = read_string(day.get_day_number(), "example01.txt")?;
+        let expected = ResultType::Nothing;
+        let result = day.part2(&lines)?;
+        assert_eq!(result, expected);
+
+        Ok(())
+    }
+
+    #[test]
+    fn parse() -> Result<()> {
+        let input = String::from("1=-0-2");
+        let snafu: Snafu = input.parse()?;
+        assert_eq!(snafu, Snafu(1747));
+        assert_eq!(snafu.as_str(), input);
+        Ok(())
+    }
+}

src/days/mod.rs

@@ -22,6 +22,7 @@ mod day21;
 mod day22;
 mod day23;
 mod day24;
+mod day25;
 mod template;
 
 pub use template::DayTrait;
@@ -31,7 +32,7 @@ pub mod day_provider {
     use super::*;
     use thiserror::Error;
 
-    const MAX_DAY: usize = 24;
+    const MAX_DAY: usize = 25;
 
     pub fn get_day(day_num: usize) -> Result<Box<dyn DayTrait>, ProviderError> {
         match day_num {
@@ -59,6 +60,7 @@ pub mod day_provider {
             22 => Ok(Box::new(day22::Day)),
             23 => Ok(Box::new(day23::Day)),
             24 => Ok(Box::new(day24::Day)),
+            25 => Ok(Box::new(day25::Day)),
             _ => Err(ProviderError::InvalidNumber(day_num)),
         }
     }