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

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

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

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

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 string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

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 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.

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

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

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 returns an array of values of an array using the Array.prototype.values() method.

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

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.

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

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

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

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

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

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

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.

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

Write a function that converts a given string to uppercase

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

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

Given a date, return the UTC date.

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

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

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

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

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 normalize method to format a string removing all the accents

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

Converts a given date to a time string

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

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

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

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

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

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

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

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

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

Create a function that counts the number of seconds in a given timestamp

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

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.

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

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

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.

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

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

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.

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

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

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

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 takes in an array of music tracks and returns an object with the count of each genre in the array

Implement a function that removes leading and trailing whitespace from a string using the String.prototype.trim() 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 removes white space at the end of a given string using String.prototype.trimEnd().

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

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 flattens nested arrays using Array.prototype.flat() method.

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

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

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 two strings as input and concatenates them using the String.prototype.concat() method.

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

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

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

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

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 two arrays, join them to create a new array.

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

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

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 takes a string and a regular expression and returns an array of all the substrings in the string that match the regular expression.

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

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

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 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 sets the UTC month of a given date object.

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

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

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

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

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