diff --git a/src/day06/main.rs b/src/day06/main.rs
index 2299e01..79f26ef 100644
--- a/src/day06/main.rs
+++ b/src/day06/main.rs
@@ -59,7 +59,8 @@ impl From<&str> for Group {
             .trim()
             .lines()
             .map(|line| {
-                line.chars().filter(|&c| c.is_alphabetic()).collect()
+                let chars: HashSet<char> = line.chars().filter(|&c| c.is_alphabetic()).collect();
+                chars
             })
             .fold(
                 "abcdefghijklmnopqrstuvwxyz".chars().collect(),