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

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

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

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

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.

Create a function that receives a Date object and returns the milliseconds that have elapsed since the start of the day.

Create a function that repeats a given string n times.

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

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

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

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

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

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

Create a function that uses the String.prototype.lastIndexOf() method to find the index of the last occurrence of a specified substring in a given string.

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

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

Write a function that checks if every element in an array satisfies a given condition.

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

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

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.

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 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.

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

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

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.

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

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

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

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

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

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

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

Write a function that returns the nth number in the Fibonacci sequence using recursion.

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

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

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().

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

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.

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

Convert a string to uppercase using String.prototype.toUpperCase();

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

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

Write a function that returns the result of a string match with a given pattern.

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

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

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 date as a number (1-31).

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

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

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

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

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.

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

Given an array of numbers and a start index, remove a certain number of elements from the array and replace them with new elements.

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.

Converts a given date to a time string

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

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

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.

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

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.

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

Implement normalize method to format a string removing all the accents

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

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

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

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.

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

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

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 counts the number of seconds in a given timestamp

Create a function that returns the current minutes.

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.

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

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

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

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.

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

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

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.

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

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.

Given an array of person objects, sort them alphabetically by their last name using String.prototype.localeCompare().

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

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

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.

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.

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

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

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.

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

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 to search for a substring in a given string using String.prototype.search() method.