// Function to add two numbers
function addNumbers(a: number, b: number): number {
  return a + b; 
}

// Attempt to add two numbers with different types (will result in runtime error)
const result = addNumbers(5, "10");

// Declaring interface of type Product
// ? indicates that the description is optional
interface Product {
  name: string;
  price: number;
  description?: string; 
}

// Function to display product information
function displayProductInfo(product: Product): void {
  console.log(`Name: ${product.name}`);
  console.log(`Price: ${product.price}`);
  // Display description if available
  if (product.description) {
    console.log(`Description: ${product.description}`); 
  } 
}

// Base class for animals
class Animal {
  constructor(public name: string) {}
  // Method to make a sound
  makeSound(): void {
    console.log(`${this.name} makes a sound`);   
  } 
}

// Subclass Dog extending Animal
class Dog extends Animal {
  // Override method to make a sound specific to the dog
  makeSound(): void {
    console.log(`${this.name} barks`);  
  } 
}

// Creating a Dog instance named "Buddy"
const myPet: Animal = new Dog("Buddy");
// Making the pet sound
myPet.makeSound();

// Function to calculate the area of a circle
function calculateArea(radius: number): number {
  return Math.PI * radius ** 2; 
}

// Given the radius of the circle
const circleRadius: number = 5;
// Calculating area
const area: number = calculateArea(circleRadius);
// Displaying the calculated area
console.log(`The area of the circle is: ${area}`);

// Interface representing a person with a name and age
interface Person {
  name: string;
  age: number;
}

// Function that greets a person by their name
function greetPerson(person: Person): string {
  return `Hello, ${person.name}!`;
}

// Creating an object of type Person
const user: Person = { name: 'Alice', age: 30 };
// Displaying a greeting message for the user
console.log(greetPerson(user));