202. Happy Number

https://leetcode.com/problems/happy-number/

Python

class Solution:
    def isHappy(self, n: int) -> bool:
        seen = set()

        while n != 1 and n not in seen:
            seen.add(n)
            current, m = 0, n
            while m > 0:
                m, remain = divmod(m, 10)
                current += remain ** 2
            n = current

        return n == 1