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

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

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

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

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

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

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 representing the desired month, and sets the month of the date to the given month.

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

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.

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

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.

Create a function that takes a string and returns a new string that is a slice of the original string. The function should take two arguments, start and end, which represent the starting and ending indices of the slice.

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 converts a given string to uppercase

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

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

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

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

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.

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

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

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

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

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

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

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

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

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

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

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 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.

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 uses String.prototype.trimEnd() to trim whitespace at the end of a 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.

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

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 concatenates a given string 'n' times using the String.prototype.repeat() 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.

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

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.

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.

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 normalizes a string using String.prototype.normalize().

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

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

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

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

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

Implement normalize method to format a string removing all the accents

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

Write a function that finds the last index of a given element in an array using the Array.prototype.findLastIndex 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 concatenates two strings using the String.prototype.concat() method. The function should take two string parameters and return the concatenated string.

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

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

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

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

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

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

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

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

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 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.

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

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.

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 replaces all instances of a given substring with another string within a larger string using String.prototype.replaceAll() 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 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 receives a string and a number n, the function should return the string repeated n times.

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

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

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

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

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

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.

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

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

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

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 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.

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

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

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

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 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 a date, return the UTC date.

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