function shuffle(array) {
for (let i = array.length - 1; i > 0; i--) {
let j = Math.floor(Math.random() * (i + 1)); // random index from 0 to i
// swap elements array[i] and array[j]
// we use "destructuring assignment" syntax to achieve that
// you'll find more details about that syntax in later chapters
// same can be written as:
// let t = array[i]; array[i] = array[j]; array[j] = t
[array[i], array[j]] = [array[j], array[i]];
}
}