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

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

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

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.

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

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

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

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

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.

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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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')

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.

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

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

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

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

Create a function that takes in a string and uses String.prototype.match() to find all occurrences of a pattern within the 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 a string and returns it in lowercase using the toLocaleLowerCase() method.

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

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

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

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

Converts a given date to a time string

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

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 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 checks if a given string ends with a specified suffix.

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

Create a function that returns the current minutes.

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 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.

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

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

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

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().

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

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

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.

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

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.

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

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

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

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

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

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 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.

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

Write a function that takes two arrays as arguments and concatenates them into a new array using the Array.prototype.concat() method.

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().

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

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

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.

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

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

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

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

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

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

Create a function that repeats a given string n times.

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

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 normalizes a string using String.prototype.normalize method.

Write a function that returns an array of char codes from a string

Given a date, return the UTC date.

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 determines if two strings are anagrams of each other.

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 an array of code points for each character in the string using String.prototype.codePointAt() method.

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

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

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

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

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.