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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.

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.

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

Write a function that takes a string and a substring, and returns the index of the first occurrence of the substring in the string. If the substring is not found in the string, return -1.

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.

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

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

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

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 counts the number of seconds in a given timestamp

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

Implement a function that returns the current month from Date object using Date.prototype.getMonth()

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().

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.

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 integer n and returns the nth Fibonacci number using recursion.

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

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

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

Write a JavaScript function to find the index of an item in an array using Array.prototype.findIndex().

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

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

Convert an array to a string with comma-separated values. The input array can contain numbers, strings, objects, or arrays.

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

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

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

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

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

Create a function that returns the current minutes.

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.

Write a function that takes a string and returns it in lowercase using the toLocaleLowerCase() 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.

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

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

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

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 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 returns the character at the specified index of a given string.

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

Implement equations using the Array.of() method to create arrays.

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

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

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

Write a function that uses the Date.prototype.getDay() method to determine the day of the week for a given date object.

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

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.

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 returns an array of char codes from a string

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

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

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

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

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 nth number in the Fibonacci sequence using recursion.

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

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

Write a function that takes a string and regular expression as inputs, and returns an array of all matches found using the String.matchAll() method.

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

Write a function that checks if a given variable is an array. If it is an array, return true, otherwise return false.

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

Converts a given date to a time string

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

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

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

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

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.

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

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

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

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

Create a function that returns the month of a Date object in UTC time zone.

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

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 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.

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

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

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

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

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

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

Write a function that flattens nested arrays using Array.prototype.flat() method.

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

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.

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

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

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 sorts an array of strings in alphabetical order using String.prototype.localeCompare()

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

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.

Write a function that takes in a date and returns the seconds within the minute in UTC time.

Implement a function that takes a Date object and a number representing minutes and sets the UTC minutes of the Date object to the provided value. The function should return the updated Date object.

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.