diff --git a/day_04/src/crossword.rs b/day_04/src/crossword.rs
index 4f609c2..1df405b 100644
--- a/day_04/src/crossword.rs
+++ b/day_04/src/crossword.rs
@@ -198,14 +198,14 @@ impl Crossword {
         self.height
     }
 
-    pub fn iter_cells(&self) -> CrosswordIterator {
+    pub fn iter_cells(&self) -> CrosswordIterator<'_> {
         CrosswordIterator {
             crossword: self,
             position: 0,
         }
     }
 
-    pub fn cell(&self, x: usize, y: usize) -> CrosswordCell {
+    pub fn cell(&self, x: usize, y: usize) -> CrosswordCell<'_> {
         CrosswordCell {
             x,
             y,