1 files changed, 22 insertions, 18 deletions

diff --git a/day1/src/main.rs b/day1/src/main.rs
index aaee00b..5931c59 100644
--- a/day1/src/main.rs
+++ b/day1/src/main.rs
@@ -7,8 +7,8 @@ use std::{
 
 #[derive(Debug, PartialEq, Eq)]
 enum Rotation {
-    Left(u16),
-    Right(u16),
+    Left(u32),
+    Right(u32),
 }
 
 #[derive(Debug)]
@@ -20,7 +20,7 @@ impl FromStr for Rotation {
     fn from_str(s: &str) -> Result<Self, Self::Err> {
         let mut chars = s.chars();
         let lr = chars.next().ok_or(ParseRotationError)?;
-        let n: u16 = chars
+        let n: u32 = chars
             .collect::<String>()
             .parse()
             .map_err(|_| ParseRotationError)?;
@@ -42,29 +42,23 @@ impl Dial {
     }
 }
 
-impl Add<u16> for Dial {
+impl Add<u32> for Dial {
     type Output = Self;
 
-    fn add(self, rhs: u16) -> Self::Output {
-        let n = self.0 as u16;
+    fn add(self, rhs: u32) -> Self::Output {
+        let n = self.0 as u32;
         let m = (n + rhs) % 100;
         Self(m as u8)
     }
 }
 
-impl Sub<u16> for Dial {
+impl Sub<u32> for Dial {
     type Output = Self;
 
-    fn sub(self, rhs: u16) -> Self::Output {
-        let n = self.0 as u16;
-
-        if rhs > n {
-            let m = 100 - (n + rhs) % 100;
-            Self(m as u8)
-        } else {
-            let m = n - rhs;
-            Self(m as u8)
-        }
+    fn sub(self, rhs: u32) -> Self::Output {
+        let n = self.0 as u32;
+        let m = (n + 100 - rhs % 100) % 100;
+        Self(m as u8)
     }
 }
 
@@ -84,11 +78,13 @@ fn main() -> anyhow::Result<()> {
         .map(|s| s.parse().map_err(|_| anyhow!("bad rotation: {}", s)))
         .collect::<anyhow::Result<_>>()?;
 
+    println!("rotations: {}", rotations.len());
+
     let mut dial = Dial::new();
     let mut zeros = 0;
 
     for rot in rotations {
-        println!("dial: {:?}", dial);
+        println!("dial: {}", dial.0);
         println!("rotation: {:?}", rot);
 
         match rot {
@@ -133,10 +129,18 @@ mod tests {
         assert_eq!(dial + 50, 0);
         assert_eq!(dial + 100, 50);
         assert_eq!(dial + 150, 0);
+        assert_eq!(dial + 2 + 48, 0);
+        assert_eq!(dial + 45 + 60, 55);
 
+        assert_eq!(dial - 45, 5);
+        assert_eq!(dial - 45 - 10, 95);
         assert_eq!(dial - 1, 49);
         assert_eq!(dial - 68, 82);
         assert_eq!(dial - 68 - 30, 52);
         assert_eq!(dial - 100, 50);
+        assert_eq!(dial - 998, 52);
+        assert_eq!(dial - 150, 0);
+        assert_eq!(dial - 51, 99);
+        assert_eq!(dial - 50, 0);
     }
 }