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Create a function that uses the copyWithin method to replace specified elements within an array.

Create a function that searches for the last index of a substring in an array using Array.prototype.lastIndexOf().

Write a function that takes a string and returns an array of matched patterns using String.prototype.matchAll().

Fill arrays with specific values using Array.prototype.fill()

This kata focuses on using String.prototype.indexOf() method.

Create a function that takes two strings as input and concatenates them using the String.prototype.concat() method.

Write a function that takes an integer n and returns the nth Fibonacci number using recursion.

Create a function that takes an array as input and returns a new array with the elements in reversed order.

Write a function that extracts a character from a string given an index using String.prototype.charAt()

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.

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.

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.

Create a function that takes a string as input and returns the string in all lowercase letters.

Given an array of objects, group the objects based on a specific key and return a map object.

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.

Create a function that returns the current date as a number (1-31).

Create a function that takes a string and a number and pads that string with a specified character until it reaches the given length.

Create a function that returns the current year using Date's built-in getFullYear method

Implement an algorithm that manages the overbooking of an airline flight.

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.

Write a function that concatenates two strings using the String.prototype.concat() method.

Write a function that returns the value of a given string using the String.prototype.valueOf() method.

Write a function that uses recursion to calculate the factorial of a given positive integer.

Write a function that can take in a list of numbers and precision cut them to a desired number of decimal places.

Write a function that uses the String.prototype.trimStart() method to remove any whitespace characters from the beginning of a given string.

Write a function that returns the index of the first occurrence of a given element in an array using Array.prototype.indexOf(). If the element is not found in the array, return -1.

Write a function that checks whether a given string ends with the specified suffix or not.

Write a function that takes a date and returns the year in the hh:mm:ss format.

Create a function that takes in a string and uses String.prototype.match() to find all occurrences of a pattern within the string.

Implement a function that takes a string as input and returns it in lower case.

Write a function that returns a substring of a given string, starting at a specified index and ending before a specified index.

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.

Implement a function that replaces all instances of a specified substring in a given string.

Create a function that takes a date and a year as arguments and returns a new date with the year set to the specified value using Date.prototype.setFullYear().

Given a date, return the UTC date.

Create a function that takes a year (YYYY) and returns the date object with its year set to the provided year.

Create a function that accepts a Set and a value to remove, and returns the updated Set after deleting the value.

Write a function that takes a Set object as a parameter and returns an array of keys using Set.prototype.keys().

Create a program that classifies music genres based on certain audio features

Create a function that normalizes a string using String.prototype.normalize method.

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.

Implement the Array.prototype.with() method that returns a new array with the elements from the original array and the added elements.

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.

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.

Replace all vowels in a string with a '-'.

Write a function that checks if an element is present in an array using Array.prototype.includes() method.

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.

Create a function that will return an array in a localized way using the toLocaleString method.

Create a Stock Advisor that recommends which stocks to buy based on certain parameters.

Write a function that takes an array and a value and pushes the value to the end of the array using Array.prototype.push().

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.

Create a function that takes an array as input and returns an array of the keys of the given array using Array.prototype.keys() method.

Complete the functions to find the index of an element in an array using Array.prototype.indexOf().

Create a function that accepts a string and a target length. If the length of the string is less than the target length, pad the string with spaces at the beginning until the target length is reached. If the string length is greater than or equal to the target length, return the original string.

Write a function that returns a substring of a given string, based on the start and end index provided

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.

Implement a function that adds a value to a set using Set.prototype.add().

Write a function that converts a given string to its string representation using the toString() method.

Create a function that takes a string and a number, and repeats the string the given number of times.

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.

Create a function that receives a string and a regular expression pattern and returns an array of all the occurrences of the pattern in the string using String.prototype.matchAll().

Write a function that takes a string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

Create a function that uses Array.prototype.entries() to iterate over an array and perform some operations.

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.

Create a function that sorts an array of strings in alphabetical order using String.prototype.localeCompare()

Write a function that takes a Date object and returns a string representing the time portion of the date in the current time zone using the toLocaleTimeString() method. The function should also take an optional argument specifying the locale to use.

Implement normalize method to format a string removing all the accents

Write a function that converts a given string to uppercase

Given an array of numbers, use reduce method to obtain a single value that represents the sum of all numbers in the array.

Implement a function that takes in a Set and returns an array of entries

Given a sentence, split it into an array of words using the String.prototype.split() method.

Create an Inventory Management System that allows users to add, remove and update items in the inventory.

Write a function that checks if a given string includes a specific substring. Use String.prototype.includes() method.

Create a function that replaces all occurrences of a substring with a new string.

Implement a function that removes all unused items in a Set collection

Create a function that takes a string and returns an array of the char codes for each character in the string

Create a function that removes white space at the end of a given string using String.prototype.trimEnd().

Implement a function that concatenates a given string 'n' times using the String.prototype.repeat() method.

Create a function that uses Array.prototype.every() to check if all the elements in an array meet a certain condition.

Convert a string to an array of Unicode code points using String.prototype.codePointAt() method.

Implement a function that returns true if a given string starts with a specific substring.

Converts a given date to a time string

Create a function that takes an array and reverse its order in place.

Create a function that replaces all instances of a given substring with another string within a larger string using String.prototype.replaceAll() method.

Create a function that takes an array and removes a portion of the array, as specified by the arguments, and returns the removed portion.

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.

Create a function that uses the String.prototype.replaceAll() method to replace all occurrences of a given substring within a string.

Complete the functions provided to properly utilize the Date.now() method.

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.

Create a function that takes a start time and an event duration and returns the end time of the event, using the Date.prototype.setHours() method to set the hours of the start time.

Create a function that transforms a given string to uppercase, using String.prototype.toLocaleUpperCase()

Create a function that takes a Date object and returns a JSON string of the date in ISO format.

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.

Implement a function that uses String's padStart method to add leading zeros to a number string to ensure it always has a minimum length

Create a function that sets the UTC month of a given date object.

Write a function that returns whether a given string ends with the provided suffix or not

Create a function that takes in a string with extra white space at the beginning and end of the string, and returns a new string with that white space removed. Use String.prototype.trim().

Write a function that joins two arrays into a single string using Array.prototype.join() method.

Write a function that takes in a string and uses precision cutting to remove all occurrences of the letter 'e'. Return the resulting string.

Create a function that greets the user depending on the current hour of the day.