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Create a function that takes a date and a year and sets the date's UTC full year to the provided year.

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.

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.

Use Array.prototype.slice() to solve the following tasks.

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

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

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.

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.

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.

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.

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

Sort an array of words based on their alphabetical order using String.prototype.localeCompare() method.

Implement a function that uses String.prototype.trimEnd() to trim whitespace at the end of a string.

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

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

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.

Write a function that takes a date string as input and converts it to a UTC date string format.

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

Write a function that replaces the first occurrence of a specific string in a given string.

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 concatenates two strings using the String.prototype.concat() method.

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

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.

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

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

Create a function that receives a string and a number n, the function should return the string repeated n times.

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

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

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

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

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.

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

Create a function that slices a string based on a given start and end indexes

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

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

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

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

Implement a function that groups an array of objects by a given key and returns a new array of objects, where each object has a key and an array of objects that have that key.

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

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.

Implement various functionalities using Array.prototype.slice() method

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

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

Implement the Array.prototype.unshift() method without using built-in functions

Create a function that takes two parameters: a string and a regular expression. The function should return an array of all matches found in the string using the regular expression.

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.

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.

Create a function that receives a string and normalizes it using the String.prototype.normalize() method. Apply the NFC normalization form.

Implement a function that takes a Date object as input and returns a formatted string

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

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

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

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

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

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

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

Converts a given date to a time string

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

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 in two parameters, a string and a substring, and checks if the string includes the substring. Return a boolean value.

Create a function that returns an array of values of an array using the Array.prototype.values() method.

Create a function that takes a string and a number as arguments, and pads the string on the right side with spaces until the string reaches the desired length.

Create a function that takes an array and a value as arguments and adds the value to the beginning of the array using the unshift() method.

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

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

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

Implement normalize method to format a string removing all the accents

Create a function that concatenates two strings using the String.prototype.concat() method. The function should take two string parameters and return the concatenated string.

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

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

Given two arrays, join them to create a new array.

Implement a function that removes leading and trailing whitespace from a string using the String.prototype.trim() method.

Write a function that finds the last index of a given element in an array using the Array.prototype.findLastIndex method.

Write a function that converts a given string to uppercase

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

Create a function that checks if a given string ends with a specified suffix.

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.

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.

Implement a function that returns the character at the specified index of a given string.

Given a date, return the UTC date.

Create a function that determines if two strings are anagrams of each other.

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

Write a function that normalizes a string using String.prototype.normalize().

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.

Implement a function that groups the elements of an array based on a given predicate function.

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.

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

Combine two arrays into a single array using the Array.prototype.concat() method

Write a function that takes in a string and a target substring, and returns the index at which the target substring is first found. If the target substring is not found in the string, return -1. Use the built-in JavaScript method `indexOf()` to solve the problem.

Implement a function that sets the milliseconds of a given date object to a specified value.

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

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.

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

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.

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

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

Write a function that takes an array of numbers and returns their sum, using Array.prototype.reduceRight().

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

Write a function that takes a Date object and returns the date formatted in the user's local format using the toLocaleDateString() method.