diff --git a/contributor_database b/contributor_database
index f33e8171a..66bbf0288 100644
--- a/contributor_database
+++ b/contributor_database
@@ -24,3 +24,7 @@ count_by:[Rohit Tanwar](@kriadmin)
 insertion_sort:[Meet Zaveri](@meetzaveri),[Rohit Tanwar](@kriadmin)
 difference_by:[Rohit Tanwar](@kriadmin)
 bubble_sort: [Shobhit Sachan](@sachans)
+has_duplicates: [Rob-Rychs](@Rob-Rychs)
+keys_only: [Rob-Rychs](@Rob-Rychs)
+values_only: [Rob-Rychs](@Rob-Rychs)
+all_unique: [Rob-Rychs](@Rob-Rychs)
\ No newline at end of file