JavaScript Interview and Coding Challenges

1. Call, Apply, and Bind Methods

In JavaScript, the call, apply, and bind methods are used to change the this context of a function.

Example:


const person = {
  name: 'John',
  greet: function(age) {
    return `Hello, my name is ${this.name} and I'm ${age} years old.`;
  }
};

const anotherPerson = { name: 'Jane' };

// Using call
console.log(person.greet.call(anotherPerson, 25)); // Hello, my name is Jane and I'm 25 years old.

// Using apply
console.log(person.greet.apply(anotherPerson, [30])); // Hello, my name is Jane and I'm 30 years old.

// Using bind
const boundGreet = person.greet.bind(anotherPerson);
console.log(boundGreet(35)); // Hello, my name is Jane and I'm 35 years old.

Try it yourself:

2. Find Factorial

A factorial of a number is the product of all positive integers less than or equal to that number. Here's an example of how to find the factorial of a number:

Example:


function factorial(n) {
  if (n === 0 || n === 1) return 1;
  return n * factorial(n - 1);
}

console.log(factorial(5)); // Output: 120