diff --git a/Questions.md b/Questions.md
index f2499c0..c6cf006 100644
--- a/Questions.md
+++ b/Questions.md
@@ -37,4 +37,4 @@
 9. [Reverse a LinkedList in groups of size k.](https://leetcode.com/problems/reverse-nodes-in-k-group/description/) `Leetcode 150` `Striver`
 10. [Rotate List](https://leetcode.com/problems/rotate-list/description/) `Leetcode 150` `Striver`
 11. [Copy List with Random Pointer](https://leetcode.com/problems/copy-list-with-random-pointer/description/) `Leetcode 150` `Striver`
-12. 
+12. [Trapping Rain Water](https://leetcode.com/problems/trapping-rain-water/description/) `Leetcode 150` `Striver`