diff --git a/contains-duplicate/SamTheKorean.py b/contains-duplicate/SamTheKorean.py
new file mode 100644
index 0000000000..e1513d0eb5
--- /dev/null
+++ b/contains-duplicate/SamTheKorean.py
@@ -0,0 +1,10 @@
+# TC : O(n) n being a length of nums array and it iterates the nums array once
+# SC : O(n) n being a size of nums array
+class Solution:
+    def containsDuplicate(self, nums: List[int]) -> bool:
+        seen = set()
+        for num in nums:
+            if num in seen:
+                return True
+            seen.add(num)
+        return False