Armstrong Number added

src/algorithms/math/armstrong.js

@@ -0,0 +1,22 @@
+// Check Armstrong Number of n Digits
+
+let number = prompt("Enter a positive integer");
+let numberOfDigits = number.length;
+let sum = 0;
+
+let temp = number;
+
+while (temp > 0) {
+
+    let remainder = temp % 10;
+
+    sum += remainder ** numberOfDigits;
+
+    temp = parseInt(temp / 10); 
+
+if (sum == number) {
+    console.log(`${number} is an Armstrong number`);
+}
+else {
+    console.log(`${number} is not an Armstrong number.`);
+}