Function isHappy

ch3-happycoin/happycoin.js:19–24

(num)

}

function isHappy(num) {
  while (num != 1n && num != 4n) {
    num = sumDigitsSquared(num);
  }
  return num === 1n;
}

function isHappycoin(num) {
  return isHappy(num) && num % 10000n === 0n;