[Solved] 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.

Table of Contents

Question

Write an algorithm to determine if a number n is happy.

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.

Return true if n is a happy number, and false if not.

Example 1:

Input: n = 19
Output: true
Explanation:
12 + 92 = 82
82 + 22 = 68
62 + 82 = 100
12 + 02 + 02 = 1

Example 2:

Input: n = 2
Output: false

Constraints:

  • 1 <= n <= 231 - 1

Python Solution

class Solution:
    def isHappy(self, n: int) -> bool:        
        s=set()
        while 1:
            n = sum([int(i)**2 for i in str(n)])
            if n in s:
                return (False)
            elif n==1:
                return (True)
            
            s.add(n)
            
                
Abhishek Sharma
Abhishek Sharma

Started my Data Science journey in my 2nd year of college and since then continuously into it because of the magical powers of ML and continuously doing projects in almost every domain of AI like ML, DL, CV, NLP.

Articles: 517

Leave a Reply

Your email address will not be published. Required fields are marked *