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

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

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

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

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

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 various functionalities using Array.prototype.slice() method

Write a function that takes a Date object and returns the date formatted in the user's local format using the toLocaleDateString() method.

Converts a given date to a time string

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

Create a function that determines if two strings are anagrams of each other.

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

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

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

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

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

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

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

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

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

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

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

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 a string and a number, and repeats the string the given number of times.

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

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

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

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

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

Given an array of numbers, use reduce method to obtain a single value that represents the sum of all numbers in the array.

Write a function that takes a string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

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

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

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

Implement a function that returns the character at the specified index of a given 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 joins two arrays into a single string using Array.prototype.join() method.

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

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

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

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

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

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

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

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

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

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 repeats a given string n times.

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

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

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 array and a value and pushes the value to the end of the array using Array.prototype.push().

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 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.

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

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

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

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

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

Write a function that converts a given string to uppercase

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 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 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.

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

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

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

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 checks if it starts with a given substring. Return a boolean indicating whether or not the string starts with the given substring.

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

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

Create a function that returns the current minutes.

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

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

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

Given a date, return the UTC date.

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

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

Sort an array of words based on their alphabetical order using String.prototype.localeCompare() 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 greets the user depending on the current hour of the day.

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

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

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

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.