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When you start learning JavaScript journey with us, you will find a structured and engaging environment designed to help you master key concepts step by step. Here’s how you can get started:

• Choose Your Category: Begin by selecting a category that matches your current focus or skill level. Whether it’s variables, control flow, loops, operators, functions, events, arrays, or strings, each category offers a set of challenges tailored to deepen your understanding and mastery.
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• Track Your Progress: Monitor your learning journey with real-time feedback. Each category displays your score, time taken, and completion status, allowing you to gauge your improvement and focus on areas that need more practice.
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• Prepare for Real-World Applications: Each exercise is designed to simulate real-world coding scenarios. By mastering these challenges, you will build the confidence and skills needed to excel in practical JavaScript development.
• Seek Guidance and Solutions: If you ever get stuck, our platform provides solutions to help you navigate through challenging exercises and deepen your understanding.

By following these steps, you will not only enhance your JavaScript skills but also enjoy a rewarding and structured learning experience that prepares you for success in JavaScript programming.

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Master JavaScript through engaging exercises that offer:

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Explore our interactive JavaScript exercises designed for both beginners and experienced developers. Master key concepts, track your progress, and prepare for real-world coding challenges. Start practicing now to sharpen your JavaScript expertise and advance your programming journey with confidence.

JavaScript Exercises – FAQs

What are javascript exercises .

JavaScript exercises are coding challenges or problems based on fill in the blanks to help you to practice and improve your JavaScript programming skills. This exercise for beginners and experienced developer.

Where can I find JavaScript exercises?

You can find JavaScript exercises on GeeksforGeeks platform with compiled set of problems. Apart from Exercises, we offer a curated JavaScript tutorial and JavaScript course to learn easily.

What are some good beginner JavaScript exercises?

For beginners, exercises like working with variables, loops, arrays, functions, and simple DOM manipulations are great starting points.

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12 JavaScript Code Challenges for Beginners

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Online courses are a great place to learn the foundations of code. But it’s when you put things into practice that you cement the concepts into your brain.

Figuring out how to solve problems and conquer coding challenges can be truly rewarding (and fun!). Stephanie, a Software Developer from Baltimore, shares why practice (including code challenges) is key to mastering a programming language :

“Codecademy is a great starting point for learning different programming languages and introducing concepts, but there’s only so much you can cover in a course. A good chunk of mastering a language is learning through experience.”

In this article, we’ll share 12 short beginner JavaScript code challenges that you can tackle. Try selecting one each day and see how you do. We’ll also share how you can continue challenging yourself and your JavaScript skills after completing our suggested list.

Top 12 JavaScript code challenges for beginners

Each of these challenges is suitable for beginners, but you may find that having a base-level knowledge of JavaScript is helpful. Or, if you have a little bit of experience, you might benefit from refreshing your knowledge with our introductory course on JavaScript .

While we don’t specify here, you can use whatever coding environment suits you best. You can use what you’re comfortable with on your local machine, or you can use the environments you’re familiar with in online JavaScript courses. Don’t forget that Google can also help if you find yourself stuck on a coding problem , but try to see if you can create a solution before heading to the search engine.

1. Print all even numbers from 0 – 10

Try to make the solution to this problem as efficiently as possible. Consider using loops that would allow you to type the fewest characters/commands. While you could simply print the even numbers, get creative and see how you could output them in a way that would work up to 10 or even up to 10,000 with little extra effort.

2. Print a table containing multiplication tables

Let’s start with the tables that many of us had to memorize in school. Can you print a table that contains all the answers to the multiplication tables from 1 through 10?

Like Challenge #1, can you create an efficient solution that you could easily expand should you need the 12 times table?

3. Create a length converter function

Creating a function is a skill that’ll be useful in many settings, and as you progress, you’ll be working on much more complicated functions than this one. But a function that converts units of measure can be pretty handy in multiple professions and industries.

Let’s start with a conversion from kilometers to miles. The function should include the input in kilometers and return the answer in miles.

4. Calculate the sum of numbers within an array

You can create your own array of numbers but consider trying this problem with a few different sets to verify your solution. Have one array with negative and positive numbers and another with integers and decimals.

You could also try using arrays of different lengths. If you’re feeling comfortable with this, try the slightly more challenging bonus challenge below.

Bonus intermediate challenge: Create a function that can return the sum of a particular column or row number in a table.

5. Create a function that reverses an array

This challenge is particularly helpful if you’re planning to become a Data Scientist . Manipulating data is a significant part of the role, and building the foundations now will help you later down the road when you’re working with large databases.

Start small here and work your way up. Begin with an array of 5 numbers, and then try your program with a larger array to verify its success.

6. Sort an array from lowest to highest

You could create a function for this solution as well, but be sure to try your program with varying lengths and types of arrays. Try one with all integers, another with negative numbers, and another with decimals.

7. Create a function that filters out negative numbers

In this challenge, you’ll have a function that takes an array as an input and returns an array. But if all goes according to plan, it’ll remove the negative numbers. This is another example of a task that’ll be useful when combing through data and looking for clever ways to eliminate “bad data.”

8. Remove the spaces found in a string

Yet another way to clean up data is to remove any errors or unnecessary spaces. This function will take in a string and then return it with all spaces removed. Think about if you were tasked with cleaning up customer data at your job. You could scale this function to clean up specific fields of data, such as zip codes.

9. Return a Boolean if a number is divisible by 10

Here, you’ll create a function that’ll give you a “true” or “false” Boolean as its output. The inputted number should only return a “true” if it’s divisible by 10. Otherwise, your program should return a “false” answer.

10. Return the number of vowels in a string

Create a function that’ll return an integer of the number of vowels found in a string. This is a great way to practice determining the features of a dataset. If you use JavaScript later in your career, you’ll be well-prepared to determine what datasets (or just strings) consist of. If you feel like an extra challenge, consider returning the number of characters.

11. Create a function that finds the maximum number in an array

In this challenge, you’ll write a function that takes an array of numbers as an input and returns the largest number in that array. Test your function with various arrays, including arrays with negative numbers, decimals, and all positive integers.

12. Check if a string is a palindrome

A palindrome is a word, phrase, number, or other sequences of characters that reads the same forward and backward (like the words “kayak,” “mom,” “radar,” and “refer”). Create a function that takes a string as input and returns a Boolean indicating whether the string is a palindrome. Test your function with different strings to ensure it works correctly.

Brush up on your JavaScript with courses and challenges

If you enjoyed putting your JavaScript skills to the test with these challenges, then consider signing up for more by downloading the Codecademy Go app . Participating in our daily or weekly challenges is an excellent way to keep your skills fresh and continue learning to solve problems.

If you wish to go a little deeper with your learning or explore more complex problems and coding challenges, consider taking an intermediate-level course. You can learn more and level up your skills to prepare for your future career with courses and Skill Paths like Create an Advanced Web App with React and Reduct or Create a Back-End App with JavaScript . So what are you waiting for? Get started today!

This blog was originally published in August 2021 and has been updated to include additional JavaScript challenges for beginners.

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Level up your JavaScript skills with 10 coding challenges

Become a Software Engineer in Months, Not Years

From your first line of code, to your first day on the job — Educative has you covered. Join 2M+ developers learning in-demand programming skills.

The best way to learn to code in JavaScript is to practice, practice, practice. That’s why today we will go over 10 coding challenges to level up your JavaScript skills . These exercises are useful for any JavaScript developer. If you’re an absolute beginner, it will be helpful to check out our beginner’s guide before diving in.

JavaScript challenges can be difficult enough without us trying to make them harder for ourselves. One of the ways to make them easier is to follow principles outlined in a short book by George Polya called How To Solve It . These steps are as follows:

• Understand the Problem
• Make a Plan
• Execute Plan
• Refactor - is There a Way to Make it Better?

As we challenge ourselves in the next ten problems, keep these steps in mind. Keep in mind that there are several ways to solve these problems. As long as you can explain your thought-process in good detail, your answer is probably fine!

Today we will cover:

• Longest String in Array
• Most Commonly Used Char in String

Two Strings Are Anagrams of Each Other

String permutation is palindrome, balanced brackets, armstrong numbers, sorting objects, reverse a linked list.

• Remove Kth-Node From Linked List
• Cyclic Linked List

Wrapping up

Longest string in an array.

Write a function that accepts an array of strings. Return the longest string.

What is our Input?

• String[] = an array of strings

What is our Output?

• String = the longest of the strings in the array

Questions to ask the interviewer:

Do we need to consider if there are no strings in the array?

• For this challenge, no

Do we need to consider times when all of the strings are the same length?

• Yes. Return the first string.

Longest String Plan

For this problem, we need to:

• Initialize and Declare Variable for Longest String
• Loop through the array
• Find the length of each string
• Determine if that length is the largest we have seen so far.
• Replace the longest/largest variable with the arr[index] as long as length is greater than the variable.
• Return longest/largest string.

Possible Solution

Explanation.

There are two different ways listed here as a possible solution to this problem: one uses the ES5 Syntax and uses the ES6 Syntax.

In both solutions, we initially need to declare a longest variable and initialize it to an empty string.

In the ES5 solution, we are utilizing a traditional for loop structure to look at each index in the array. We are using the array method forEach to iterate over the array in the ES6 solution.

As we iterate through the data structure, we want to take a look at the length of each string. In JavaScript, we can do that with the length property.

In the ES5 solution, we utilized a conditional statement to see if the current ( arr[i] ) string’s length is longer than (but not equal to) the current longest string( longest ). The ES6 solution takes another approach with using the Math object property max as a shortcut for the conditional logic in the ES5 version.

If the string is longer, we assign it to the longest variable we already created.

Return the longest as our function’s terminal statement in both cases.

Most Commonly Used Character in String

Write a function that takes a string, and returns the character that is most commonly used in the string.

• String = one String

What is Our Output?

• String = the single character that shows up the most in the given string

Do we need to consider if there is no string given?

Do we need to consider times when more than one character shows up the same number of times?

• No. Return the last one.

Most Used Char Plan

To find the character most often used in a string, we need to be able to count how many of each kind we have. We can do this using an object that has key:value pairs.

• Define and Initialize an object
• Map character count to that object.
• Loop through the object to find the max count.
• Assign new max count value to maxCharCount and new max key to maxChar .
• Return maxChar

Create a charCount object. This object can be named whatever you’d like as long as it’s consistent.

Use a standard for loop to iterate through the string, and check to see if it exists in the charCount object. If it does, add 1 to CharCount[key] and reassign it to the same variable. The pipes here will cover any instance where the key does not yet exist in the object and initialize the count to 1.

Loop through the object using a for...in loop. This type of loop allows us to iterate over each property in an object to look at its value. In this instance we want to find the largest number.

The wording for this problem indicates that they want us to find the last max number (in the case there is more than one character with the same amount of appearances), so we use >= to reassign the maxChar if needed.

Return our maxChar .

Create a function that takes in two strings as two parameters and returns a boolean that indicates whether or not the first string is an anagram of the second string.

• String , String = two Strings
• Boolean are either true or false . True if they are anagrams of each other, and false if they are not.

What is an anagram?

• An anagram is another word or phrase formed by rearranging letters of the first word or phrase.

Do we need to consider whitespace?

• Trim whitespace prior to comparison.

Anagrams Plan

If an anagram is just a bunch of letters jumbled around, we can see if the strings are anagrams of each other by:

Comparing the length: if they are not same length, they are not an anagram of the other

Sorting the string and using an equality operator to see if it’s equal.

There are a couple of different ways to solve this problem.

• Compare the length of the first string to the length of the second string. If they are not equal, return false .
• If the strings pass the initial check, we sort each individual string, assign it to a variable, and then return the result of setting the variables equal to each other. If they are equal, it will return true . If not, it will return false .

This particular solution considers white space by sorting it to the end of the string, so it doesn’t necessarily matter if it’s counted or not.

Given a string, write a function that will return whether or not that string is a palindrome.

• Boolean means either true or false . true if string is a palindrome; false if it is not.
• Do not trim whitespace.

Does the palindrome need to be in the dictionary?

• No, it does not.

Palindromes Plan

• Reverse the string. We need to keep the old reference to the string to use later. To do this, we need to split string into an array.
• Reverse the string.
• Join the string.
• See if new variation of string is equal to an old variation of string.

This one is deceptively simple. You just need to have knowledge of array methods and how to work with strings in conjunction with those methods. Practice how this could possibly be done without the methods so you know how these methods work under the hood.

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The Complete Guide to Modern JavaScript

Given a string possibly containing three types of braces ( {} , [] , () ), write a function that returns a Boolean indicating whether the given string contains a valid nesting of braces.

• Boolean means either true or false . true if string has balanced brackets; false if it does not.

What do you mean by balanced brackets?

• A string is considered balanced if it has as many opening brackets of a given type as it has closing brackets of that same type. No bracket can be left unmatched. A closing bracket also cannot match a corresponding opening bracket that comes after it. Brackets also cannot overlap each other.

Will the string only have brackets in it?

• No. All chars can be used.

Balanced Brackets Plan

Because we are looking for nested balanced brackets, we are looking to use a data structure to store the open brackets we have seen so far.

As we come to a closing bracket, we need to look to see if the last bracket added to the data structure matches the opposite of the current bracket.

If your data structure is empty by the time we get to the end of the string, we have balanced brackets.

The process for this particular problem is more about checking for failures. We use a data structure called a stack that takes a first in, last out approach to do that.

When we come across an open bracket, we push it on to the stack. When we come across a closed one, we check to see if the last index of the stack is the opposite the current character.

If the stack is empty by the time we get to the end of our logic, we have balanced brackets.

An Armstrong number is an n-digit number that is equal to the sum of the n t h nth n t h powers of its digits. Determine if the input number is an Armstrong number. Return either true or false.

• Number = n-digit number
• Boolean means either true or false . true if number is Armstrong Number; false if it is not.

May I have an example please?

• 1 3 + 5 3 + 3 3 = 153 1^3 + 5^3 + 3^3 = 153 1 3 + 5 3 + 3 3 = 153

Armstrong Number Plan

Remember that in JavaScript type coercion exists. When working with Numbers is JS, remember to check the typeof the number. If it is a string, you’ll need to plan for that. This is really important when working with math in JS.

To solve this problem, we change the number to a string, figure out the power by getting the length of the number, and then use a for loop to add up the individual numbers ^ length of the number passed in.

We then check to see if the sum is equal to the original number. If it is, it is an Armstrong number.

Given an array of objects, sort the objects by population size. Return the entire object.

• An array of objects
• An array of objects, sorted by population

SortObjects Plan

JavaScript has a built-in array method called sort() that we can use for this particular exercise.

What’s interesting about this particular method is that in JavaScript, if you don’t use a callback compare function to sort the array of objects, the default sort method is used to sort by characters rather than number. For example:

We need to use a compare function as a callback passed into the sort method to make sure that the actual numbers are treated properly.

To sort an array of objects by a certain property, we have to use the compare function as a parameter in the built-in sort method in JavaScript.

The compare function takes in two parameters: here they are named a and b . They represent two objects next to each other in our array. If a and b are both objects, we can use dot notation to access the property population .

If we want to be sure that the array has objects sorted by population in increasing order, we evaluate a.population - b.population . If it’s -1, it will put the list in decreasing order by population. The opposite would put it in increasing order. If the expression happens to evaluate to 0, it means that the two patterns are equal to the other.

Create a Node class and a LinkedList class with these methods:

• insertFirst(data)
• insertLast(data)
• Nothing. We are building two classes from scratch that have methods.
• This is a class that will create instances of a LinkedList. We will use it to test the reverse a linked list functionality.

Questions to Possibly Ask Interviewer

Are we to assume this is a singly-linked list that actually exists?

• No. Handle all possible errors if you can.

Reverse a Linked List Plan

The first thing we need to investigate is how a linked list works. Once we have that figured out, it might be a lot easier to write out the code for it.

Linked lists are different from arrays in that they don’t require a continuous place of residence in memory. Linked Lists can be broken up into single nodes if needed as long as the linked list’s next value is not null.

Let’s plan to initialize three variables: prev as NULL, curr as head, and next as NULL. Iterate trough the Linked List. In a while loop, do the following.

• Store next node
• next = curr.next
• Change next of current (this is where the reversing happens)
• curr.next = prev

We start with the Node class. It will have a data property and a next property. The next property acts as a pointer that will direct us to the next node in our linked list if it exists, or null.

For the Linked List class, we check for failures in our methods before we handle the success. With Linked Lists, we will check to see if the actual list exists by checking to see if the head exists and perform the appropriate logic for each method.

When we reverse a linked list, juggling variables around is the rule of the day. We have one variable, node, that is declared and then initialized to head. We declare tmp and prev without initializing them.

While the node exists, we redirect the pointers by reassigning variables. The result is a reversed linked list.

Remove Kth-Node from Linked List

Using the Node and LinkedList classes that you created in the previous question, add methods to it so that, when given an kth-integer, you can delete that k t h kth k t h node from the linked list

• We will add to the Linked List and Node classes that were written in the previous question.
• This is a class that will create instances of a LinkedList. We will use it to test delete a k t h kth k t h -node functionality.

Is this a zero-based indexing?

LinkedList Delete K-th Node Plan

When given K we have to be able to delete that node in a linked list. To handle edge cases, we need to have some knowledge of the size of the list, the node prior to the Kth node and the node after the Kth node. We essentially need to redirect the pointers for those nodes to not include the one we want to be deleted.

To do that, we’ll loop through the list, keep track of which node we’re on, and change the pointers to skip the Kth-node. It’ll still be in memory, ready to be written over, but it will be essentially deleted from our list.

Circular Linked List

Given a linked list, return true if the list is circular, false if it is not.

• A new LinkedList()

A Boolean that tells us if the linked list is circular or not.

What does it mean for a linked list to be circular?

• It means that a next node value could point to a node that we have already seen in our linked list.

We will have two pointers: one slow and one fast. The fast one will move twice as much as the slow one on each iteration. If it comes to be that the fast.next.next value doesn’t exist, we can assume it’s a linear linked list. If the slow pointer and the fast pointer ultimately end up equal, we know we have a circular component to our list.

Here we declare and initialize two pointers, one slow and one fast, that are both pointed at the head. While the next two nodes exist, we’ll reassign the pointers: the slow will move to the next node and the fast will move two nodes.

If the slow ever is the same value as the fast, we have a circular linked list. If ever one of the two nodes past the current node doesn’t exist, we’ll break the loop and return false.

Congrats! You’ve gone through 10 JavaScript coding challenges! One of the best things to do when encountering a problem is to use Georges Polya’s practices. Once we understand the problem, we make a plan and try to reiterate an unsolved problem. This way, you are more likely to break down the problem into smaller manageable components.

Solving these problems takes practice. You’ll develop an intuition for algorithms the more time you put into practicing. So don’t worry if it doesn’t come to you right away. Keep practicing!

Educative’s course The Complete Guide to Modern JavaScript walks you through the basics of the language and all the new features introduced up to 2020. After following this course, functions and variables let , const , generators, promises and async won’t be a problem anymore.

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Practice 148 exercises in JavaScript

Learn and practice JavaScript by completing 148 exercises that explore different concepts and ideas.

Explore the JavaScript exercises on Exercism

Unlock more exercises as you progress. They’re great practice and fun to do!

15 Best Platforms To Practice JavaScript self.__wrap_b=(t,n,e)=>{e=e||document.querySelector(`[data-br="${t}"]`);let s=e.parentElement,r=R=>e.style.maxWidth=R+"px";e.style.maxWidth="";let o=s.clientWidth,i=s.clientHeight,c=o/2-.25,l=o+.5,u;if(o){for(;c+1 {self.__wrap_b(0,+e.dataset.brr,e)})).observe(s)};self.__wrap_b(":Rid9j6:",1)

HackerEarth

Freecodecamp, geeksforgeeks, educative.io, codeacademy, javascript questions – by lydia hallie, javascript coding practice – by learning zone, 123 essential javascript questions – by yuri katkov, javascript interview question – by sudheer j.

Learning any programming language is not enough, and we need to practice.

If you are learning JavaScript, I have curated the ten best platforms to practice JavaScript for free.

Codedamn is an interactive programming platform; you will learn and build projects side by side. It offers over 500+ coding problems for you to practice.

You can solve 3-5 questions daily without waiting another day to solve more questions.

Codedamn has community support, if you get stuck on a particular problem, you can ask for help, and developers will be ready to help you anytime.

The problem’s difficulty level ranges from easy to hard. But you can go at your pace.

Here is the link to solve 500+ JavaScript problems .

If you think these problems are too advanced, you can learn about JavaScript basics, which codedamn offers for free.

Link to learn JavaScript: JavaScript basics

On codewars, you will get all types of questions ranging from easy to complex.

You will get instant feedback on your answers. Your rank will level up as you progress.

If you get stuck, codewars have a senior developers community that will help you.

Link to practice on codewars

codin games is a gamified learning platform. On codin games, you will code and execute the correct code to save yourself from obstacles and enemies.

You can compete individually or by teaming up with other fellow developers.

You can compare your and other developer code to improve your JavaScript coding skills.

You can play and build your developer profile, and You can even apply for jobs. You need to solve complex problems and be consistent on the platform to stand out from others.

Link to practice on the codin game.

If you don’t know Solo Learn, you are not a developer. Earlier, Solo learn was only available as a mobile application, and now you can also learn on the web.

Solo learn offers a JavaScript course and exercise to improve your JavaScript coding skills.

At the end of each topic, you will get practice problems you need to solve to unlock the next section.

Link to practice on Solo learn .

Edabit has interactive exercises ranging from easy to complex, and you can filter the challenges using tags. You can practice your JavaScript coding skills for free.

If you get stuck on any question, you can unlock the solution, but you will lose the XPs you have gained.

Alternatively, the resources tab contains the concepts to learn to solve that problem.

Link to practice JavaScript at edabit.

Hacker earth has a set of questions based on if you are preparing for an interview or you are a beginner at programming ,

It has a codemonk section where you will get questions based on Data Structures and algorithms. Best suited if you know DSA and algorithms, or you can practice easy and medium-difficulty problems.

On hacker earth, you can participate in challenges, try to build your developer profile, and stand out from other developers. And apply for jobs at companies.

Link to practice at HackerEarth

On programiz, you can practice JavaScript for free, and You will get the list of concepts to learn and practice problems at the end of each concept to retain what you have learned.

There are separate JavaScript examples sections available there, and you will find the JavaScript-related question and some general programming questions based on the topics you have learned.

Link to practice JavaScript examples at programiz.

Freecodecamp is popular among developers because of its ocean of totally free courses.

Freecodecamp offers 100s of exercises related to JavaScript, ranging from basic concepts, regular expressions, array methods, objects, data structure, and algorithms.

These exercises are for beginners to advanced javascript developers.

Link to practice on freecodecamp

To practice on GeeksforGeeks, you need to create an account once you create an account with them, head over to the below link to practice JavaScript.

This platform best suits you if you have Data Structure and algorithms knowledge.

You can filter out the problems based on the companies that have asked about that problem or on the concepts like Arrays, Objects, and Strings.

You can even choose the problem difficulty level from school to pro level.

Link to practice on GeeksforGeeks

The Educative has an assessment test. You can take the JavaScript assessment test, which takes around 20 minutes to complete.

The assessment test consists of all the topics, from fundamental concepts like variables, data types, and conditional statements to advanced concepts like arrays and objects.

Link to the assessment test

On Codecademy, you will find a javascript project-based course that is very helpful if you want to learn and build projects at the same time using javascript.

Link to javascript courses

I have curated four GitHub repositories that are helpful. You will gain problem-solving skills, and some repositories will help you prepare for the interview.

This repo has more than 500+ questions with answers, and this repo is available in 18 other languages. In this repo, you will find basic to very advanced questions, and some are very difficult.

Link to repo

This repo has more than 100+ javascript exercises with the answers. This repo will give you insights into How the recruiter will ask questions in a javascript-related interview.

You will find 123 essential javascript interview-related questions, which you can practice on your code editor or online to crack practical interviews. This repo has 4K stars, and you will find some exciting questions that might help you build problem-solving skills.

You will find 1000+ questions ? related to javascript on this repo, which you can practice. Questions range from the difficulty level of beginners to advanced.

I hope you found this article helpful, You can choose any platform and practice it to improve your developer profile, gain problem-solving skills and move to the next platform.

Thanks for reading.

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Curious about this topic? Continue your journey with these coding courses:

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Kata Library: JavaScript Practice

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Collections are a way for you to organize kata so that you can create your own training routines. Every collection you create is public and automatically sharable with other warriors. After you have added a few kata to a collection you and others can train on the kata contained within the collection.

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Set the name for your new collection. Remember, this is going to be visible by everyone so think of something that others will understand.

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17 JavaScript for/while loop exercises with solutions

1. write a js code to print numbers from 1 to 10.

Function `printNumbers()` prints numbers from 1 to 10 using for loop.

2. Write a JS code to print a 2D array

3. write a js code to print even numbers in given array.

Function `printEven()` prints all the even numbers of a 2D array using for loops and ‘%’ operator.

4. Write a JS code to delete all occurrence of element in given array

Function `deleteElement()` deletes all the occurrence of element from the given array.

5. Write a JS code to demonstrate Async loop

For loop consisting of setTimeout() function to print loop variable 5 times in asynchronous way.

6. Write a JS code to find the power of a number using for loop

Function numPower() to returns power of number for provided exponential value using for loop.

7. Write a JS code to print a pattern using for loop

Function printPattern() is used to print a pattern for a given range using nested for loop.

8. Write a JS code to find the no of digits in a number

Function digitCount() to returns the number of digits in a given number using while loop.

9. Write a JS code to calculate the sum of digits in a number

10. write a js code to find the largest number in an array.

Program to find the largest number in the given 1D array. 

11. Write a JS code to find the number of zeros in 2D Matrix

12. write a js code to find product of two arrays.

Function findProd() to generate a new array which is the product of two arrays of the same size using for loop.

13. Write a JS code to print the Fibonacci series for a given value of N

The function fibonacci() prints the Fibonacci series for the given range N using While loop.

14. Write a JS code to find N value in the Fibonacci series for a given number

The function Findfibonacci() prints the index of number in the Fibonacci series if present or “element not present” if the number is not part of the Fibonacci series.

15. Write a JS code to count all letters in a word

16. write a js code to find duplicate values in a given array.

Function findDup() to returns all the elements that are repeated more than once in a given array.

17. Write a JS code for binary search algorithm

JavaScript Loop tutorials

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