Dsa
Math
Hard
Happy Number Differentiation
A happy number is defined by the following process: repeatedly replace the number with the sum of the squares of its digits until the number equals 1 (where it will stay), or it loops endlessly in a cycle that does not include 1. Write a program that determines if a number N is happy or not. The input consists of a single integer N (1 <= N <= 10^6). Output 'HAPPY' if it is happy and 'SAD' otherwise.
Example Input:
19
Example Output:
HAPPY
Key concepts
number theorymathhappy numbers
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