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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.

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.

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

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 normalize method to format a string removing all the accents

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

Create a function that repeats a given string n times.

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 returns an array of char codes from a 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 object and returns the date formatted in the user's local format using the toLocaleDateString() method.

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

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

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

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

Write a function that takes a Set object as a parameter and returns an array of keys using Set.prototype.keys().

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 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 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 an array as input and returns an array of the keys of the given array using Array.prototype.keys() method.

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

Create a function that accepts a Set and a value to remove, and returns the updated Set after deleting the value.

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

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

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 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 takes an integer n and returns the nth Fibonacci number using recursion.

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

Given a date, return the UTC date.

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 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().

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

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

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

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

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

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

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

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

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 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.

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.

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

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.

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

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

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

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

Create a function that takes in an array of music tracks and returns an object with the count of each genre in the array

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

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

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

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

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.

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

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.

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

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

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

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.

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.

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

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

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

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

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

Write a function that converts a given string to uppercase

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

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

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 sets the UTC month of a given date object.

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

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

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

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

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.

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

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

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

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

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

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

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

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 returns the current year using Date's built-in getFullYear method

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

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

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

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

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