Solution: Happy Number

Statement

Write an algorithm to determine if a number $num$ is a happy number.

We use the following process to check if a given number is a happy number:

• Starting with the given number $num$, replace the number with the sum of the squares of its digits.
• Repeat the process until:
  • The number equals $1$, which will depict that the given number $num$ is a happy number.
  • It enters a cycle, which will depict that the given number $num$ is not a happy number.

Return TRUE if $num$ is a happy number, and FALSE if not.

Constraints

• $1 \leq$ num $\leq 2^{31} - 1$