let pets = ['Dog', 'Cat', 'Hamster'];

console.log('Before');
console.log(pets);
console.log(`\n----------------------------------------------\n`);

// method 1
const add1 = pets[3] = 'Squirrel'

console.log(`pets[3] returns element: ${add1}`);
console.log('\nAfter');
console.log(pets);

const add2 = pets[5] = 'Hedgehog'

console.log(`\n\npets[5] returns element: ${add2}`);
console.log('\nAfter');
console.log(pets);

console.log(`\n----------------------------------------------\n`);

// method 2
pets = ['Dog', 'Cat', 'Humster'];

const push = pets.push('Betta Fish');

console.log(`returns element: ${push}`);
console.log('\nAfter');
console.log(pets);

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

  1. https://codepen.io/nullobject/pen/cngzI.js