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Happy Number

Problem statement​

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.

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

Example 1:

Input: n = 19Output: trueExplanation:12 + 92 = 8282 + 22 = 6862 + 82 = 10012 + 02 + 02 = 1

Example 2:

Input: n = 2Output: false

Constraints:

  • 1 <= n <= 231 - 1

My solution​

/**
 * @param {number} n
 * @return {boolean}
 */
var isHappy = function(n) {
    const tracker = new Set();
    
    
    return traverse(n, tracker)
};

function traverse(n, tracker) {
    // console.log(tracker)
    if (tracker.has(n)) {
        return false
    }
    
    tracker.add(n);
    
    let currentSum = 0;
    while (n > 0) {
        currentSum += Math.pow(n % 10, 2);
        n = Math.floor(n / 10)
    }
    
    if (currentSum === 1) {
        return true
    }
    
    return traverse(currentSum, tracker)
}