# Introduction In this lab, we will explore how to use the `uniqueElementsByRight()` function in JavaScript to find the reversed unique values of an array based on a provided comparator function. We will learn how to use `Array.prototype.reduceRight()` and `Array.prototype.some()` methods to create an array containing only the last unique occurrence of each value based on the comparator function provided. By the end of this lab, you will have a better understanding of how to manipulate arrays in JavaScript using these methods.
Click the virtual machine below to start practicing