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

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

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

Write a function that converts a given string to its string representation using the toString() method.

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 regular expression pattern and returns an array of all the occurrences of the pattern in the string using String.prototype.matchAll().

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

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

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

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

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

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 and reverse its order in place.

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

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.

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 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.

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 an array of the keys of the given array using Array.prototype.keys() method.

Create a function that returns the current minutes.

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

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

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 the String.prototype.lastIndexOf() method to find the index of the last occurrence of a specified substring in a given string.

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

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

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

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

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.

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.

Write a function that takes in a string and uses precision cutting to remove all occurrences of the letter 'e'. Return the resulting 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.

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

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

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 receives a string and a number n, the function should return the string repeated n times.

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.

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

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

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

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

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

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 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 greets the user depending on the current hour of the day.

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

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

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

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.

Implement normalize method to format a string removing all the accents

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

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

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.

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

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

Converts a given date to a time 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.

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

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 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 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 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 a number as parameters. The function should return the string repeated `n` times, where n is the number passed as parameter.

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

Given a date, return the UTC date.

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

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

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

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().

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

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

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

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

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

Create a function that repeats a given string n times.

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

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

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

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

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.

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

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

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

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

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.

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

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