Library
easy
String Slice Kata
Create a function that slices a string based on a given start and end indexes
medium
Slice and Dice
Use Array.prototype.slice() to solve the following tasks.
medium
Date ToString Kata
Implement a function that takes a Date object as input and returns a formatted string
easy
String code point kata
Write a function that takes a string and returns an array of code points for each character in the string using String.prototype.codePointAt() method.
easy
Last Occurrence of a Substring in a String
Write a function that takes a string and a substring as arguments, and finds the last occurrence of the substring in the string. If the substring is not found, return -1.
medium
Slice Challenge
Write a function that takes a string and returns all its substrings of length 3 or greater. You must use String.prototype.slice() to achieve this.
easy
String Repeat Kata
Implement a function that concatenates a given string 'n' times using the String.prototype.repeat() method.
easy
String Slice Kata
Create a function that takes a string and returns a new string that is a slice of the original string. The function should take two arguments, start and end, which represent the starting and ending indices of the slice.
easy
String Padding Kata
Create a function that takes a string and a number and pads that string with a specified character until it reaches the given length.
easy
String to Uppercase kata
Convert a string to uppercase using String.prototype.toUpperCase();
easy
UTC Month Setter
Create a function that sets the UTC month of a given date object.
easy
Last Index Of Substring Kata
Create a function that searches for the last index of a substring in an array using Array.prototype.lastIndexOf().
medium
Array ToSpliced
Create a function that takes an array and removes a portion of the array, as specified by the arguments, and returns the removed portion.
easy
Date Time Conversion
Converts a given date to a time string
medium
Find Last Exercise
Create a function that uses Array.prototype.findLast() to find the last element in an array that matches a given condition. Return the element if it exists or null if it does not.
easy
Trimming White Space at End of String
Create a function that removes white space at the end of a given string using String.prototype.trimEnd().
easy
Set Seconds Kata
Write a function that takes a date object and a number of seconds and returns a new date object with the seconds set to the provided value.
Example input: setSeconds(new Date('2022-10-10T10:10:10'), 30)
Expected output: new Date('2022-10-10T10:10:30')
easy
String.charAt() Kata
Write a function that accepts a string and a number as arguments, then returns the character at that position in the string. Use String.prototype.charAt() for this exercise.
medium
Airline Overbooking
Implement an algorithm that manages the overbooking of an airline flight.
easy
Array.of() Exercise
Implement equations using the Array.of() method to create arrays.
medium
Music genre classification
Create a program that classifies music genres based on certain audio features
easy
Trim Ending Spaces
Write a function that takes a string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().
easy
String Char Code Kata
Write a function that returns an array of char codes from a string
easy
Reversed Array
Create a function that takes an array as input and returns a new array with the elements in reversed order.
easy
String to Local Uppercase Kata
In this kata, you will be working with the String.prototype.toLocaleUpperCase() method to convert a string to uppercase according to the user's locale.
easy
Substring Kata
Given a string, return a new string that is a substring of the original string. The substring should start at a specified index and continue until the end of the original string.
medium
Precision Cutting Kata
Write a function that takes in a string and uses precision cutting to remove all occurrences of the letter 'e'. Return the resulting string.
easy
Date.toLocaleDateString() Kata
Write a function that takes a Date object and returns the date formatted in the user's local format using the toLocaleDateString() method.
easy
Unicode Kata
Write a function that checks if a given string has a unicode character code point greater than or equal to 128. Use the String.prototype.codePointAt() method.
easy
Char Code Getter
Create a function that takes a string and returns an array of the char codes for each character in the string
easy
Split and Join String Exercise
Write a function that takes a string as input and splits it into an array of words using String.prototype.split(). Then, join the array back into a string using Array.prototype.join(). Finally, return the new string with a different delimiter separating each word.
easy
Joining Arrays Kata
Write a function that joins two arrays into a single string using Array.prototype.join() method.
medium
String Replace All Kata
Create a function that replaces all instances of a given substring with another string within a larger string using String.prototype.replaceAll() method.
easy
Date Prototype Get Date
Create a function that returns the current date as a number (1-31).
easy
String IndexOf Kata
Create a function that takes two parameters: a string and a target substring, and returns the index of the first occurrence of the target substring in the string. If the target substring is not found, return -1.
easy
Set Add Kata
Implement a function that adds a value to a set using Set.prototype.add().
easy
Sum of numbers using reduceRight()
Write a function that takes an array of numbers and returns their sum, using Array.prototype.reduceRight().
medium
String Replace All Kata
Create a function that uses the String.prototype.replaceAll() method to replace all occurrences of a given substring within a string.
easy
String ReplaceAll Kata
Implement a function that replaces all instances of a specified substring in a given string.
easy
Lowercase Kata
Create a function that takes a string as input and returns the string in all lowercase letters.
easy
String Concatenation Kata
Create a function that concatenates two strings using the String.prototype.concat() method.
easy
String repeat Kata
Create a function that receives a string and a number as parameters. The function should return the string repeated `n` times, where n is the number passed as parameter.
easy
String StartsWith Kata
Implement a function that returns true if a given string starts with a specific substring.
easy
String includes
Create a function that takes in two parameters, a string and a substring, and checks if the string includes the substring. Return a boolean value.
easy
Lowercase Kata
Write a function that takes a string and returns it in lowercase using the toLocaleLowerCase() method.
easy
Sort Alphabets with localeCompare()
Create a function that sorts an array of strings in alphabetical order using String.prototype.localeCompare()
easy
Search for Substring Kata
Create a function to search for a substring in a given string using String.prototype.search() method.
easy
UTC Date Converter
Write a function that takes a date string as input and converts it to a UTC date string format.
medium
Set.prototype.has() Exercise
Implement a function that checks if all elements from an array are included in a given Set using the built-in Set.prototype.has() method.
medium
Array Grouping Kata
Implement a function that groups the elements of an array based on a given predicate function.
easy
Set Entries Kata
Implement a function that takes in a Set and returns an array of entries
easy
Substring Kata
Write a function that returns a substring of a given string, based on the start and end index provided
medium
Date UTC Full Year
Create a function that takes a date and a year and sets the date's UTC full year to the provided year.
easy
Every Check
Write a function that checks if every element in an array satisfies a given condition.
easy
Get UTC Seconds
Write a function that takes in a date and returns the seconds within the minute in UTC time.
medium
String Normalize Kata
Implement normalize method to format a string removing all the accents
easy
Get UTC Month
Create a function that returns the month of a Date object in UTC time zone.
easy
Convert Date to JSON String
Create a function that takes a Date object and returns a JSON string of the date in ISO format.
easy
String to Uppercase
Create a function that takes a string as input and returns the same string in uppercase letters using the `toString()` method of the String object.
easy
Normalize String Kata
Create a function that normalizes a string using String.prototype.normalize method.
easy
Pad Start Kata
Create a function that takes in a string and a length and returns a new string with the original string padded with leading spaces if it is shorter than the provided length.
easy
Hourly Greeting
Create a function that greets the user depending on the current hour of the day.
easy
Substring Kata
Write a function that returns a substring of a given string, starting at a specified index and ending before a specified index.
medium
Array copyWithin Kata
Create a function that uses the copyWithin method to replace specified elements within an array.
easy
Date setMonth() Kata
Write a function that takes a date object and a number representing the desired month, and sets the month of the date to the given month.
easy
String trimStart() Method
Write a function that uses the String.prototype.trimStart() method to remove any whitespace characters from the beginning of a given string.
medium
Recursive Fibonacci Sequence
Write a function that returns the nth number in the Fibonacci sequence using recursion.
easy
Array Concat Kata
Combine two arrays into a single array using the Array.prototype.concat() method
medium
String Match Kata
Create a function that takes in a string and uses String.prototype.match() to find all occurrences of a pattern within the string.
easy
Anagram Checker
Create a function that determines if two strings are anagrams of each other.
medium
Music Genre Classification
Create a function that takes in an array of music tracks and returns an object with the count of each genre in the array
medium
Grouping Arrays to Map
Given an array of objects, group the objects based on a specific key and return a map object.
medium
Stock Advisor
Create a Stock Advisor that recommends which stocks to buy based on certain parameters.
easy
Array Index Kata
Complete the functions to find the index of an element in an array using Array.prototype.indexOf().
easy
Date Year Calculator
Create a function that returns the current year using Date's built-in getFullYear method
medium
Split String Kata
A kata that requires the student to use String.prototype.split() to split a given string into substrings and perform a specified operation on them.
medium
setYear() Method
Create a function that takes a year (YYYY) and returns the date object with its year set to the provided year.
easy
String Search Kata
Write a function that takes a string and a search term and returns the index of the first occurrence of the search term in the given string. If the search term is not present in the string, return -1.
easy
Date Set UTC Seconds
Write a function that accepts a date object and a number of seconds (0 - 59) and returns a new date object with the seconds set to the provided value. The operation should be done using the setUTCSeconds() method.
medium
Array Entries Kata
Create a function that uses Array.prototype.entries() to iterate over an array and perform some operations.
easy
CharAt Kata
Implement a function that returns the character at the specified index of a given string.
easy
String StartsWith
Create a function that takes in a string and checks if it starts with a given substring. Return a boolean indicating whether or not the string starts with the given substring.
easy
Find Last Index Kata
Write a function that takes an array and a value as arguments and returns the index of the last occurrence of that value in the array using Array.prototype.lastIndexOf(). If the value is not found, return -1.
medium
Find Last Index Kata
Write a function that finds the last index of a given element in an array using the Array.prototype.findLastIndex method.
easy
String includes kata
Implement a function that takes an array of strings and a search string, and returns a new array containing only the strings that includes the search string using String.prototype.includes() method.
easy
Set forEach Kata
Write a function that loops through a Set using Set.prototype.forEach() method and returns an array containing the results of applying the provided function to each element.
easy
Splitting Strings
Given a sentence, split it into an array of words using the String.prototype.split() method.
easy
Concatenation Kata
Write a function that concatenates two strings using the String.prototype.concat() method.
easy
String Replace Kata
Replace all vowels in a string with a '-'.
easy
Current Minutes
Create a function that returns the current minutes.
medium
Match Substrings in a String
Write a function that takes a string and a regular expression and returns an array of all the substrings in the string that match the regular expression.
easy
String endsWith Kata
Create a function that checks if a given string ends with a specified suffix.
easy
Set Keys Kata
Write a function that takes a Set object as a parameter and returns an array of keys using Set.prototype.keys().
medium
Array Index Finder
Create a function that takes an array of numbers and returns the index of a given element. Use Array.prototype.findIndex() to implement the function.
easy
Sort names using localeCompare()
Given an array of person objects, sort them alphabetically by their last name using String.prototype.localeCompare().
easy
UTC Date
Given a date, return the UTC date.
easy
EndsWith Kata
Write a function that checks whether a given string ends with the specified suffix or not.
easy
Date.prototype.getYear() Kata
Write a function that takes a date and returns the year in the hh:mm:ss format.
medium
Array Slice and Splice
Given an array of numbers and a start index, remove a certain number of elements from the array and replace them with new elements.
medium
Array Slice Kata
Implement various functionalities using Array.prototype.slice() method