feat: add number of 1 bits solution

Author: mangodm-web

number-of-1-bits/dm.py

@@ -0,0 +1,6 @@
+class Solution:    
+    def hammingWeight(self, n: int, acc: int = 0) -> int:
+        if n == 0:
+            return acc
+        
+        return self.hammingWeight(n // 2, acc + n % 2)