diff --git a/docs/heap/Add-Merge-k-sorted-lists.md b/docs/heap/Add-Merge-k-sorted-lists.md
index 4109734f6..99ffead98 100644
--- a/docs/heap/Add-Merge-k-sorted-lists.md
+++ b/docs/heap/Add-Merge-k-sorted-lists.md
@@ -1,5 +1,5 @@
 ---
-id: Heap-data-Structure-4
+id: heap-data-structure-4
 title: heap data structure
 sidebar_label: Merge k Sorted Lists
 sidebar_position: 11
diff --git a/docs/heap/Median-of-a-stream.md b/docs/heap/Median-of-a-stream.md
index ad4ef6aca..ef5add07d 100644
--- a/docs/heap/Median-of-a-stream.md
+++ b/docs/heap/Median-of-a-stream.md
@@ -1,5 +1,5 @@
 ---
-id: Heap-data-Structure-5
+id: heap-data-structure-5
 title: heap data structure
 sidebar_label: Find Median of a Stream
 sidebar_position: 12