Happy Number

A happy number is defined by the following process:

1. Starting with any positive integer, replace the number by the sum of the squares of its digits.
2. Repeat the process until the number either equals 1 (where it will stay), or it loops endlessly in a cycle that does not include 1.

Numbers for which this process ends at 1 are happy. Return true if n is a happy number, and false otherwise.

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Example 1

Input: n = 19
Output: true
Explanation: 1^2 + 9^2 = 82 -> 8^2 + 2^2 = 68 -> 6^2 + 8^2 = 100 -> 1^2 + 0^2 + 0^2 = 1

Example 2

Input: n = 2
Output: false
Explanation: 2 -> 4 -> 16 -> 37 -> 58 -> 89 -> 145 -> 42 -> 20 -> 4 (cycle detected, never reaches 1)

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Constraints

• 1 <= n <= 2^31 - 1