Check if All Array Elements Are Unique

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Introduction

In this lab, we will explore the concept of checking whether all elements in an array are unique using JavaScript. We will use the Set object to eliminate duplicate elements and compare the length of the unique values to the original array. This lab will provide a hands-on experience on how to check for unique elements in an array using JavaScript.


Skills Graph

%%%%{init: {'theme':'neutral'}}%%%% flowchart RL javascript(("`JavaScript`")) -.-> javascript/BasicConceptsGroup(["`Basic Concepts`"]) javascript/BasicConceptsGroup -.-> javascript/variables("`Variables`") javascript/BasicConceptsGroup -.-> javascript/data_types("`Data Types`") javascript/BasicConceptsGroup -.-> javascript/arith_ops("`Arithmetic Operators`") javascript/BasicConceptsGroup -.-> javascript/comp_ops("`Comparison Operators`") javascript/BasicConceptsGroup -.-> javascript/obj_manip("`Object Manipulation`") subgraph Lab Skills javascript/variables -.-> lab-28141{{"`Check if All Array Elements Are Unique`"}} javascript/data_types -.-> lab-28141{{"`Check if All Array Elements Are Unique`"}} javascript/arith_ops -.-> lab-28141{{"`Check if All Array Elements Are Unique`"}} javascript/comp_ops -.-> lab-28141{{"`Check if All Array Elements Are Unique`"}} javascript/obj_manip -.-> lab-28141{{"`Check if All Array Elements Are Unique`"}} end

How to Check if All Array Elements Are Unique

To check if all elements in an array are unique, follow these steps:

  1. Open the Terminal/SSH and type node to start practicing coding.
  2. Create a new Set from the mapped values to keep only unique occurrences.
  3. Use Array.prototype.length and Set.prototype.size to compare the length of the unique values to the original array.

Here's an example function that implements these steps:

const allUnique = (arr) => arr.length === new Set(arr).size;

You can use this function to check if an array has all unique elements like this:

allUnique([1, 2, 3, 4]); // true
allUnique([1, 1, 2, 3]); // false

Summary

Congratulations! You have completed the Check if All Array Elements Are Unique lab. You can practice more labs in LabEx to improve your skills.

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