Frontend Challenges

JavaScript Challenges

Master the fundamentals of JavaScript, through challenges that cover the core concepts of the language.

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81

Challenges Solved

Trapping Rain Water

#533

hard

javascript

arrays

two-pointers

#513

medium

javascript

#515

easy

javascript

First Bad Version

#468

medium

javascript

#471

easy

javascript

Immutability Helper

#474

medium

javascript

#480

easy

javascript

#483

easy

javascript

Find Corresponding Node

#486

easy

javascript

Detect Data Type

#489

medium

javascript

#491

medium

javascript

#496

hard

javascript

#498

medium

javascript

#501

medium

javascript

Reorder Array with New Indexes

#503

easy

javascript

Object.assign()

#506

medium

javascript

clearAllTimeout()

#509

easy

javascript

#511

medium

javascript

Debounce with Leading & Trailing

#459

medium

javascript

#465

medium

javascript

Curry with Placeholder

#455

medium

javascript

#449

easy

javascript

Snake to CamelCase

#439

easy

javascript

#442

medium

javascript

#446

medium

javascript

Throttle with Leading and Trailing

#432

medium

javascript

throttle

performance

#405

medium

javascript

#409

medium

javascript

Parallel async execution

#411

easy

javascript

async

concurrency

Html string encoder

#413

hard

javascript

string

parsing

test and expect

#415

medium

javascript

testing

jest

#418

medium

javascript

dom

parsing

Promise.finally

#420

easy

javascript

promises

Execute Promises in Series

#422

medium

javascript

promises

async

Promise.allSettled

#424

medium

javascript

promises

polyfill

Priority-based Promise Executor

#426

hard

javascript

promises

async

find-highest-commodity-price

#403

medium

javascript

array

algorithm

search

#358

easy

javascript

#356

easy

javascript

#346

easy

javascript

promises

Promise Resolution Order

#348

easy

javascript

promises

Promise Chain Output

#350

easy

javascript

promises

Promise Chain Output 2

#352

easy

javascript

promises

#161

easy

javascript

#158

medium

javascript

#145

easy

javascript

#148

easy

javascript

#152

medium

javascript

#141

easy

javascript

Overriding constructor

#137

easy

javascript

Class and Prototype

#133

easy

javascript

#121

easy

javascript

F.prototype and constructor

#123

easy

javascript

forEach and this

#115

easy

javascript

#117

easy

javascript

#113

easy

javascript

#109

easy

javascript

Queue using Stack

#104

easy

javascript

#99

easy

javascript

closure

#95

easy

javascript

#91

easy

javascript

Array.prototype.reduce

#82

medium

javascript

#86

easy

javascript

Array.prototype.filter

#74

easy

javascript

Array.prototype.map

#78

easy

javascript

Two functions - one object

#69

easy

javascript

objects

#66

easy

javascript

objects

Logical Operators

#61

easy

javascript

logical operators

#58

medium

javascript

events

#55

medium

javascript

performance

#43

hard

javascript

promise

#35

hard

javascript

#37

hard

javascript

InstanceOfClass

#32

easy

javascript

#18

easy

javascript

utility

lodash

#20

hard

utility

lodash

javascript

#10

medium

javascript

#13

medium

javascript

lodash

#8

easy

closure

javascript

#7

easy

javascript

promise

event loop

#6

hard

javascript

closure

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