JavaScript Programs
105 Essential Programs from Beginner to Advanced
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Hello World
#1Print Hello World
Print Name
#2Print user name
Add Two Numbers
#3Add two numbers
Swap Numbers
#4Swap two numbers using temp
Largest of Two
#5Find largest of two numbers
Even or Odd
#6Check even or odd
Factorial
#7Find factorial of number
Fibonacci
#8Print Fibonacci series
Reverse Number
#9Reverse digits
Prime Check
#10Check prime number
Palindrome String
#11Check palindrome string
Largest in Array
#12Find largest element
Remove Duplicates
#13Remove duplicates from array
Second Largest
#14Find second largest
Count Vowels
#15Count vowels in string
Sum of Digits
#16Sum digits
GCD
#17Find GCD
Power
#18Power of number
Leap Year
#19Check leap year
Character Frequency
#20Frequency count
Prime Range
#21Print primes till 10
Armstrong Number
#22Check Armstrong number
Palindrome Number
#23Check palindrome number
Count Digits
#24Count digits in number
Print Numbers 1 to N
#25Print numbers from 1 to N
Even Numbers 1 to 10
#26Print even numbers
Sum of First N Numbers
#27Find sum of first N numbers
Multiplication Table
#28Print table of a number
Largest of Three Numbers
#29Find largest among three numbers
Positive or Negative
#30Check positive or negative number
Sort Array Ascending
#31Sort array in ascending order
Reverse String
#32Reverse a string
Find LCM
#33Find LCM of two numbers
Second Largest in Array
#34Find second largest element
Simple Calculator
#35Perform basic operations
Function Expression vs Declaration
#36Difference between function declaration and expression
Arrow Functions Example
#37Usage of arrow functions
Callback Function Demo
#38Passing function as argument
Closure Example
#39Understanding closures
Hoisting Example
#40Variable and function hoisting
IIFE Example
#41Immediately Invoked Function Expression
Default Parameters
#42Default function parameters
Rest Parameters
#43Rest operator usage
Higher Order Function
#44Functions returning functions
Recursion Example
#45Function calling itself
Array Map Example
#46Transform array using map
Array Filter Example
#47Filter elements from array
Array Reduce Example
#48Reduce array to single value
Find Duplicate Elements
#49Find duplicates in array
Merge Two Arrays
#50Merge arrays using spread operator
Flatten Nested Array
#51Flatten multi dimensional array
Group Objects by Property
#52Group array of objects by key
Sort Array of Objects
#53Sort objects by property
Deep Clone Object
#54Deep copy objects
Count Occurrences in Array
#55Frequency count in array
Anagram Check
#56Check two strings are anagram
First Non-Repeating Character
#57Find first unique character
Longest Word
#58Find longest word in sentence
String Compression
#59Compress repeating characters
Reverse Each Word
#60Reverse words individually
Capitalize First Letter
#61Capitalize each word
Word Frequency Counter
#62Count word frequency
setTimeout Example
#63Timer execution demo
Promise Example
#64Basic promise usage
Async Await Demo
#65Async await syntax
Fetch API Example
#66Fetch data from API
Promise.all Example
#67Handle multiple promises
Create Dynamic List
#68Create list using DOM
Form Validation
#69Validate form fields
Debounce Function
#70Debounce implementation
Event Loop Demo
#71Demonstrate JavaScript event loop
Call Stack Example
#72Visualize call stack
Memory Leak Example
#73Create memory leak with closures
Garbage Collection Demo
#74Objects removed from memory
Custom Bind
#75Implement bind
Custom Call
#76Implement call
Custom Apply
#77Implement apply
Custom Promise
#78Basic custom promise
Retry Promise
#79Retry async task
Promise Queue
#80Sequential promises
Async Scheduler
#81Run async tasks in order
Promise Timeout
#82Timeout wrapper
Parallel vs Sequential
#83Compare async execution
Throttle Function
#84Throttle implementation
Advanced Debounce
#85Debounce implementation
Memoization
#86Cache function result
Lazy Loading
#87Lazy load image
Web Worker
#88Worker messaging
Stack
#89Stack implementation
Queue
#90Queue implementation
Linked List
#91Simple linked list
Binary Search
#92Binary search array
Quick Sort
#93Quick sort
LRU Cache
#94Simple LRU
Singleton Pattern
#95Singleton implementation
Observer Pattern
#96Observer demo
Pub Sub
#97Publish subscribe
Module Pattern
#98Module pattern
Factory Pattern
#99Factory pattern
Custom Router
#100SPA router
Infinite Scroll
#101Infinite scroll demo
Drag and Drop
#102Drag drop demo
File Upload Preview
#103Preview file
Mini State Management
#104Redux style store
Virtual DOM Demo
#105Virtual DOM concept
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