diff --git a/day2/src/main.rs b/day2/src/main.rs
index 72e4b6c..a6364c3 100644
--- a/day2/src/main.rs
+++ b/day2/src/main.rs
@@ -10,12 +10,9 @@ enum Symbol {
 impl From<char> for Symbol {
     fn from(value: char) -> Self {
         match value {
-            'A' => Self::Rock,
-            'B' => Self::Paper,
-            'C' => Self::Scissors,
-            'X' => Self::Rock,
-            'Y' => Self::Paper,
-            'Z' => Self::Scissors,
+            'A' | 'X' => Self::Rock,
+            'B' | 'Y' => Self::Paper,
+            'C' | 'Z' => Self::Scissors,
             _ => panic!("invalid input"),
         }
     }
diff --git a/day3/src/main.rs b/day3/src/main.rs
index d320553..0005f1e 100644
--- a/day3/src/main.rs
+++ b/day3/src/main.rs
@@ -3,12 +3,12 @@ use std::{collections::HashSet, fs::read_to_string};
 use color_eyre::{eyre::*, Result};
 use itertools::Itertools;
 
-fn priority(item: &char) -> usize {
+fn priority(item: char) -> Result<usize> {
     ('a'..='z')
-        .position(|c| *item == c)
+        .position(|c| item == c)
         .map(|i| i + 1)
-        .or_else(|| ('A'..='Z').position(|c| *item == c).map(|i| i + 27))
-        .unwrap_or(0)
+        .or_else(|| ('A'..='Z').position(|c| item == c).map(|i| i + 27))
+        .ok_or_else(|| eyre!("invalid character '{}'", item))
 }
 
 fn initial(input: &str) -> (usize, usize) {
@@ -20,7 +20,7 @@ fn initial(input: &str) -> (usize, usize) {
             let compartment2 = compartment2.chars().collect::<HashSet<_>>();
             compartment1
                 .intersection(&compartment2)
-                .map(priority)
+                .filter_map(|v| priority(*v).ok())
                 .sum::<usize>()
         })
         .sum();
@@ -32,7 +32,7 @@ fn initial(input: &str) -> (usize, usize) {
             group
                 .map(|line| line.chars().collect::<HashSet<_>>())
                 .coalesce(|a, b| Ok(a.intersection(&b).copied().collect()))
-                .map(|set| set.iter().map(priority).sum::<usize>())
+                .map(|set| set.iter().filter_map(|v| priority(*v).ok()).sum::<usize>())
                 .sum::<usize>()
         })
         .sum();