Add Digits problem solved

Author: hasibulislam999

Daily Challenges/258_add-digits.js

@@ -0,0 +1,21 @@
+/**
+ * Title: Add Digits
+ * Description: Given an integer num, repeatedly add all its digits until the result has only one digit, and return it.
+ * Author: Hasibul Islam
+ * Date: 26/04/2023
+ */
+
+/**
+ * @param {number} num
+ * @return {number}
+ */
+
+var addDigits = function (num) {
+  num = num.toString();
+  let newNumber = 0;
+  for (let i = 0; i < num.length; i++) {
+    newNumber += Number(num[i]);
+  }
+  if (newNumber.toString().length === 1) return newNumber;
+  return addDigits(newNumber);
+};