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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().

Write a function that concatenates two strings using the String.prototype.concat() 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 checks if a given string ends with a specified suffix.

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

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 determines if two strings are anagrams of each other.

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

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

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.

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 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.

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

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

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

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

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

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

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

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 a date and a year and sets the date's UTC full year to the provided year.

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

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

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 returns the result of a string match with a given pattern.

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

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

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

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.

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

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

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

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 an array of numbers and returns the index of a given element. Use Array.prototype.findIndex() to implement the function.

This kata focuses on using String.prototype.indexOf() 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 Date object and returns the milliseconds that have elapsed since the start of the day.

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 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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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.

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

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

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 returns the character at the specified index of a given string.

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

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

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.

Convert a string to an array of Unicode code points using String.prototype.codePointAt() method.

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

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

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

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

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

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

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

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

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 returns the current month from Date object using Date.prototype.getMonth()

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

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

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

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

Create a function that returns the current minutes.

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

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

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

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.

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

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

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

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 uses the copyWithin method to replace specified elements within an array.

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

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