Write an algorithm to determine if a number
n 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.
- 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.
n is a happy number, and
false if not.
class Solution: def isHappy(self, n: int) -> bool: def calculate_happy(num): sum_ = 0 # sum of square of each digit while num: sum_ += (num % 10) ** 2 num = num // 10 return sum_ # record record = set() while True: n = calculate_happy(n) if n == 1: return True # if an element repeats in set, means we are in a loop if n in record: return False else: record.add(n)