diff --git a/src/alt.rs b/src/alt.rs
index 3b3c0c6..4afb7f0 100644
--- a/src/alt.rs
+++ b/src/alt.rs
@@ -137,7 +137,8 @@ impl LandmarkBestSet<'_> {
         results.reverse();
 
         self.best_landmarks.clear();
-        for result in results[..self.best_size].iter() {
+
+        for result in results[..(self.best_size.min(results.len()))].iter() {
             self.best_landmarks.push(result.0);
         }
     }