diff --git a/number-of-1-bits/ppxyn1.py b/number-of-1-bits/ppxyn1.py
index 3762a12b3e..15a65772f3 100644
--- a/number-of-1-bits/ppxyn1.py
+++ b/number-of-1-bits/ppxyn1.py
@@ -1,5 +1,7 @@
 # idea: - 
 
+# Ans 1
+# Time Complexity: O(N) ?
 from collections import Counter
 class Solution:
     def hammingWeight(self, n: int) -> int:
@@ -8,3 +10,13 @@ def hammingWeight(self, n: int) -> int:
 
 
 
+# Ans 2
+# Time Complexity: O(N) 
+class Solution:
+    def hammingWeight(self, n: int) -> int:
+        cnt = 0
+        while n:
+            cnt += n & 1 # check current bit
+            n >>= 1 # move to next bit
+        return cnt
+