make sure its interger and make sure negative numbers are handled properly

Author: G4EVA-dev

src/index.ts

@@ -18,16 +18,13 @@ const PORT = process.env.PORT || CONFIG.DEFAULT_PORT;
 app.use(cors());
 app.use(express.json());
 
-app.get("/", (req: Request, res: Response) => {
-  res.send(CONFIG.ROOT_ROUTE_MESSAGE);
-});
-
 app.get("/api/classify-number", async (req: Request, res: Response) => {
   try {
     const numberParam = req.query.number as string;
     const number = parseInt(numberParam);
 
-    if (isNaN(number)) {
+    // Validate integer input
+    if (isNaN(number) || !Number.isInteger(number)) {
       return res.status(400).json({
         number: numberParam,
         error: true,
@@ -62,5 +59,5 @@ app.get("/api/classify-number", async (req: Request, res: Response) => {
 });
 
 app.listen(PORT, () => {
-  console.log(`Server is running on http://localhost:${PORT}`);
+  console.log(`Server is running on port ${PORT}`);
 });

src/utils/mathUtils.ts

@@ -1,37 +1,39 @@
-import { CONFIG } from "../config";
-
 export function isPrime(n: number): boolean {
-  if (n <= CONFIG.MIN_NUMBER || n > Number.MAX_SAFE_INTEGER) return false;
-  for (let i = CONFIG.MIN_DIVISOR; i <= Math.sqrt(n); i++) {
-    if (n % i === 0) return false;
+  const absN = Math.abs(n);
+  if (absN <= 1) return false;
+  for (let i = 2; i <= Math.sqrt(absN); i++) {
+    if (absN % i === 0) return false;
   }
   return true;
 }
 
 export function isPerfect(n: number): boolean {
-  if (n <= CONFIG.MIN_NUMBER) return false;
-  let sum = CONFIG.MIN_NUMBER;
-  for (let i = CONFIG.MIN_DIVISOR; i <= Math.sqrt(n); i++) {
-    if (n % i === 0) {
+  const absN = Math.abs(n);
+  if (absN <= 1) return false;
+  let sum = 1;
+  for (let i = 2; i <= Math.sqrt(absN); i++) {
+    if (absN % i === 0) {
       sum += i;
-      if (i !== n / i) sum += n / i;
+      if (i !== absN / i) sum += absN / i;
     }
   }
-  return sum === n;
+  return sum === absN;
 }
 
 export function isArmstrong(n: number): boolean {
-  const digits = String(n).split("");
+  const absN = Math.abs(n);
+  const digits = String(absN).split("");
   const length = digits.length;
   const sum = digits.reduce(
     (acc, digit) => acc + Math.pow(Number(digit), length),
     0
   );
-  return sum === n;
+  return sum === absN;
 }
 
 export function calculateDigitSum(n: number): number {
-  return String(n)
-    .split("")
-    .reduce((acc, digit) => acc + Number(digit), 0);
+  const sign = n < 0 ? -1 : 1;
+  const digits = Math.abs(n).toString().split("");
+  const sum = digits.reduce((acc, digit) => acc + Number(digit), 0);
+  return sign * sum;
 }