MohammedA

task-1/count-above-threshold.js

@@ -1 +1,15 @@
 //Your code here
+function countAboveThreshold(numbers, threshold) {
+  if (!Array.isArray(numbers)) return 0;
+  return numbers.reduce(
+    (count, n) => (typeof n === "number" && n > threshold ? count + 1 : count),
+    0,
+  );
+}
+
+module.exports = { countAboveThreshold };
+
+//Example Usage
+countAboveThreshold([1, 5, 10, 3], 4); // returns 2
+countAboveThreshold([7, 8, 9], 10); // returns 0
+countAboveThreshold([], 5); // returns 0

task-2/calculateAverage.test.js

@@ -0,0 +1,35 @@
+import { describe, it, expect } from "vitest";
+import { calculateAverage } from "./calculateAverage";
+
+describe("calculateAverage", () => {
+  it("returns the average for a normal array of valid numbers", () => {
+    // [2, 4, 6] → (2 + 4 + 6) / 3 = 4
+    expect(calculateAverage([2, 4, 6])).toBe(4);
+  });
+
+  it("returns the number itself when the array contains only one value", () => {
+    expect(calculateAverage([5])).toBe(5);
+  });
+
+  it("returns null when the array is empty", () => {
+    expect(calculateAverage([])).toBeNull();
+  });
+
+  it("returns null when the input is not an array", () => {
+    expect(calculateAverage("123")).toBeNull();
+    expect(calculateAverage(null)).toBeNull();
+    expect(calculateAverage(undefined)).toBeNull();
+    expect(calculateAverage(42)).toBeNull();
+  });
+
+  it("returns null when the array contains a non-number value", () => {
+    expect(calculateAverage([1, 2, "3"])).toBeNull();
+    expect(calculateAverage([10, true, 20])).toBeNull();
+    expect(calculateAverage([5, {}, 15])).toBeNull();
+  });
+
+  it("correctly handles negative and decimal numbers", () => {
+    // (-2 + 4.5 + 1.5) / 3 = 1.333...
+    expect(calculateAverage([-2, 4.5, 1.5])).toBeCloseTo(1.3333, 4);
+  });
+});