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

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

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

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

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

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 sets the UTC month of a given date object.

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

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

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

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

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.

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

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

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.

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.

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

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 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 uses the Date.prototype.getDay() method to determine the day of the week for a given 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 to search for a substring in a given string using String.prototype.search() method.

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

Write a function that replaces the first occurrence of a specific string in a given string.

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

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

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

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

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

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

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

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

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.

Implement normalize method to format a string removing all the accents

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

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 removes all unused items in a Set collection

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

Create a function that repeats a given string n times.

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 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 normalizes a string using String.prototype.normalize method.

Sort an array of words based on their alphabetical order using String.prototype.localeCompare() 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 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 a string and returns an array of the char codes for each character in the string

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

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.

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

Create a function that returns the current minutes.

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.

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

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.

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

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

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

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

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

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

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.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 if an element is present in an array using Array.prototype.includes() method.

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

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

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

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

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

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

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

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

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.

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

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

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

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

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

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

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

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

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

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

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

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 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.

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

Write a function that takes two arrays as arguments and concatenates them into a new array using the Array.prototype.concat() 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 an array and a value and pushes the value to the end of the array using Array.prototype.push().