Write an algorithm to determine if a number is "happy".
A happy number is a number defined by the following process: Starting with any positive integer, replace the number by the sum of the squares of its digits, and repeat the process until the number equals 1 (where it will stay), or it loops endlessly in a cycle which does not include 1. Those numbers for which this process ends in 1 are happy numbers.
Example: 
Input: 19
Output: true
Explanation: 
12 + 92 = 82
82 + 22 = 68
62 + 82 = 100
12 + 02 + 02 = 1
class Solution:
     def isHappy(self, n):
         """
         :type n: int
         :rtype: bool
         """
         if n < 0:
             return False
         if n == 1:
             return True
         
         my_set = set()
         
         while n not in my_set:
             my_set.add(n)
             sq_sum = 0
             while n > 0:
                 remain = n%10
                 print(('r', remain))
                 sq_sum += int(remain * remain)
                 n = int(n/10)
             print(sq_sum)
             if sq_sum == 1:
                 return True
             else:
                 n = sq_sum
               
 
         return False
                 

class Solution:
     def isHappy(self, n):
         """
         :type n: int
         :rtype: bool
         """
         if n < 0:
             return False
         if n == 1:
             return True
         
         my_set = set()
         
         while n not in my_set:
             my_set.add(n)
             sq_sum = 0
             while n > 0:
                 remain = n%10
                 print(('r', remain))
                 sq_sum += int(remain * remain)
                 n = int(n/10)
             print(sq_sum)
             if sq_sum == 1:
                 return True
             else:
                 n = sq_sum
               
 
         return False
                 
