diff --git a/src/main.rs b/src/main.rs
index 4016a33..dbfa669 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -32,9 +32,8 @@ fn remove_doubles(characters: &Vec<char>) -> Vec<char> {
 
     characters
         .iter()
-        .enumerate()
-        .filter(|(idx, _)| !shortenable_map[*idx])
-        .map(|(_, itm)| *itm)
+        .zip(shortenable_map)
+        .filter_map(|(c, shortenable)| if shortenable { None } else { Some(*c) })
         .collect()
 }