How To ...

alternate case of each character in a string

  • for-loop | modulo operator | toLowerCase | toUpperCase
  • for loop | split | join | toLowerCase | toUpperCase
  • map | split | join | toLowerCase | toUpperCase

    • calculate average of array

  • for loop | length
  • forEach | length
  • reduce | length

    • calculate sum of all numbers in an array

  • for loop
  • forEach
  • recursion | slice | length
  • reduce

    • capitalize first letter of each word in an array

  • for loop | charAt | slice | toUpperCase | toLowerCase
  • forEach | charAt | slice | toUpperCase | toLowerCase
  • map | charAt | slice | toUpperCase | toLowerCase

    • capitalize first letter of each word in a string

  • for-loop | charAt | slice | split | join | toLowerCase | toUpperCase
  • map | charAt | slice | split | join | toLowerCase | toUpperCase
  • regular expression | replace | toLowerCase | toUpperCase

    • capitalize Nth character in a string

  • slice | toLowerCase | toUpperCase

    • check if a string contains another string

  • includes
  • indexOf

    • check if all characters in a string are unique

  • for loop | object
  • for-loop | Set

    • check if number is prime

  • for loop | modulo operator
  • for loop | Math.sqrt | modulo operator

    • check if string is a palindrome

  • BUILT-IN METHODS | regex | replace | split | reverse | join | toLowerCase
  • for-loop | regex | replace | length | toLowerCase

    • check if two strings are anagrams of each other

  • BUILT-IN METHODS | regex | replace | split | sort | join | length | toLowerCase
  • CHARACTER FREQUENCY MAP | Object.keys | length | regex | replace | for...of loop | for...in loop
  • Object | for loop | for...in loop | regEx | replace | length | toLowerCase

    • compare two arrays for equality

  • every | length
  • for loop | length
  • JSON.stringify

    • connect to an API

  • axios | async | await | promise | try | catch | json
  • axios | then | catch | promise | json
  • fetch | async | await | promise | try | catch | json
  • fetch | then | catch | promise | json
  • xmlHttpRequest | open | onload | status | responseText | onerror | send

    • convert array elements to upper or lower case

  • for loop | toLowerCase | toUpperCase
  • forEach | toLowerCase | toUpperCase
  • map | toLowerCase | toUpperCase

    • convert string to camel case

  • map | split | charAt | slice | join | trim | toLowerCase | toUpperCase
  • reduce | split | charAt | slice | trim | toLowerCase | toUpperCase

    • convert string to kebab case

  • reduce | trim | split | regex | toLowerCase
  • replace | trim | toLowerCase | regex

    • convert string to pascal case

  • map | split | charAt | slice | join | toLowerCase | toUpperCase
  • reduce | split | charAt | slice | trim | toLowerCase | toUpperCase

    • convert string to snake case

  • reduce | trim | split | regex | toLowerCase
  • replace | regex | trim | toLowerCase

    • convert string to title case

  • for loop | split | charAt | slice | join | toLowerCase | toUpperCase
  • reduce | split | charAt | slice | toLowerCase | toUpperCase
  • replace | regex | toUpperCase

    • convert temperature

  • celsius to fahrenheit and kelvin
  • fahrenheit to celsius and kelvin
  • kelvin to celsius and fahrenheit

    • count frequency of each element in an array

  • for loop | Object
  • for...of loop | Object
  • forEach
  • reduce

    • count number of words in a string

  • filter | trim | split | regex
  • for...of loop | regular expression | test
  • for loop | trim | split | length
  • match | regular expression | length
  • matchAll | regular expression | Array.from | length
  • reduce | trim | split | regex
  • split | trim | regular expression | length

    • count occurrences of a character in a string

  • for loop (case-insensitive)
  • for loop (case-sensitive)
  • split | length

    • count odd and even numbers in an array

  • for loop | modulo operator
  • forEach | modulo operator
  • reduce | modulo operator

    • count vowels in a string

  • filter | includes | Array.from | length
  • for loop | toLowerCase
  • for...of loop | includes | toLowerCase
  • reduce | includes | Array.from
  • reduce | indexOf | Array.from
  • match | regular expression | length
  • replace | regular expression | length

    • extract initials from a string

  • for...of loop | split | charAt | toUpperCase
  • map | split | charAt | join | toUpperCase
  • match | regex | join | toUpperCase

    • find difference between two arrays

  • filter | includes
  • for loop | indexOf | push
  • reduce | indexOf | push
  • Set | filter | has
  • Set | difference

    • find factorial of a number

  • for loop
  • recursion
  • while loop

    • find first non-repeated character in a string

  • find | indexOf | lastIndexOf
  • for loop | indexOf | lastIndexOf
  • for loop | slice | includes | charAt
  • for...of loop | Map | set | get
  • for...of loop | object

    • find intersection of two arrays

  • filter | includes
  • forEach | includes | push
  • reduce | includes | push
  • Set | for...of loop | has | push
  • Set | intersection

    • find longest word in a string

  • for...of loop | split | length
  • reduce | split | length
  • sort | split | length

    • find maximum difference between two numbers in an array

  • for loop
  • for loop | Math.max | Math.min
  • Math.max | Math.min
  • nested for loops | Math.abs
  • reduce | Math.max | Math.min

    • find maximum number in an array

  • for loop
  • reduce
  • sort

    • find minimum and maximum number in an array

  • for loop
  • sort

    • find minimum number in an array

  • for loop
  • reduce
  • sort

    • find Nth maximum number in an array

  • sort - [duplicates allowed]
  • sort | Set - [duplicates removed]

    • find Nth minimum number in an array

  • sort - [duplicates allowed]
  • sort | Set - [duplicates removed]

    • find power of number

  • exponentiation operator
  • for loop
  • Math.pow
  • recursion

    • find Nth root of number

  • exponentiation operator
  • Math.pow

    • find symmetric difference between two arrays

  • filter | includes
  • reduce | indexOf | push
  • Set | filter | has
  • Set | for...of loop | has | push
  • Set | symmetricDifference

    • find union of two arrays

  • concat | filter | indexOf
  • reduce | concat | includes | push
  • Set | spread syntax
  • Set | push
  • Set | union

    • generate countdown

  • promise | async | await | resolve | setInterval | clearInterval
  • promise | resolve | setInterval | clearInterval
  • recursion | setTimeout
  • setInterval | clearInterval

    • generate fibonacci sequence up to n terms

  • for loop | slice - [ return as an array ]
  • for loop - [ print to console ]
  • recursion | for loop - [ print to console ]
  • while loop | slice - [ return as an array ]
  • while loop - [ print to console ]

    • generate lottery numbers

  • Set | size | add | while loop | Math.random | Math.floor | Array.from | sort

    • generate pattern

  • CHESS BOARD PATTERN | for loop | modulo operator
  • TRIANGLE PATTERN | for loop

    • generate random color

  • hex | for loop | Math.random | Math.floor
  • hex | Math.random | Math.floor | toString | padStart
  • hex | Math.random | Math.floor | toString | slice
  • hsl | Math.random | Math.floor
  • rgb | Math.random | Math.floor

    • generate random numbers

  • Math.random | Math.floor | Math.ceil

    • inverse case of a string

  • for loop | toLowerCase | toUpperCase
  • for loop | charCodeAt | fromCharCode | toLowerCase | toUpperCase

    • merge two or more arrays

  • concat
  • push
  • spread syntax

    • merge two arrays with alternative values

  • for loop | push | Math.max | length
  • reduce | push | concat | slice | length
  • while loop | push | length

    • remove duplicates from an array

  • filter | indexOf
  • for loop | includes | push
  • forEach | includes | push
  • reduce | includes
  • reduce | indexOf | push
  • Set

    • remove falsy values from an array

  • filter | Boolean
  • for loop | push

    • repeat a string

  • for loop
  • Array | join
  • recursion
  • repeat
  • while-loop

    • reverse a string

  • split | reverse | join
  • for loop
  • for...of loop
  • forEach | split
  • recursion | substring | charAt
  • reduce | split
  • DECREMENTING WHILE LOOP | while loop
  • TWO POINTER METHOD | while loop | split | join

    • reverse order of words in a string

  • BUILT-IN METHODS | split | reverse | join
  • for loop | split | trim
  • reduce | split | trim

    • solve FizzBuzz problem

  • for loop | modulo operator | push - [ return as an array ]
  • for loop | modulo operator - [ print to console ]
  • recursion | modulus operator | length | push | join - [ return as an array ]
  • switch | for-loop | modulo operator - [ print to console ]
  • for-loop | modulo operator | ternary operator - [ print to console ]
  • while-loop | modulo operator - [ print to console ]
  • FizzBuzz with user inputs | for loop - [ print to console ]

    • solve the two sum problem

  • BRUTE FORCE SOLUTION | nested for loops
  • HASH MAP SOLUTION | Map | has | get | set | for loop
  • TWO POINTER SOLUTION | map | sort | while loop | length

    • sort an array

  • BUBBLE SORT | for loop
  • BUBBLE SORT | while loop | for loop
  • BUILT-IN SORT | sort numbers | sort | slice
  • BUILT-IN SORT | sort strings | sort | slice | localeCompare | toLowerCase
  • BUILT-IN SORT | sort numbers & strings | sort | slice | localeCompare
  • INSERTION SORT | for loop | while loop
  • MERGE SORT | recursion | while loop | slice | push | Math.floor | concat | length
  • QUICK SORT | recursion | for loop | push
  • SELECTION SORT | nested for loops
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