Solve 202. Happy Number

python/202_happy_number.py

@@ -0,0 +1,16 @@
+class Solution:
+    def isHappy(self, n: int) -> bool:
+        seen = {n}
+        while True:
+            n = self.square_digital_sum(n)
+            if n in seen:
+                return n == 1
+            seen.add(n)
+
+    @staticmethod
+    def square_digital_sum(n: int) -> int:
+        total = 0
+        while n > 0:
+            n, digit = divmod(n, 10)
+            total += digit**2
+        return total