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

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.

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.

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

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

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

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

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.

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.

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

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

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

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

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

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.

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

Write a function that converts a given string to uppercase

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

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

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

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

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

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

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 checks if a given string ends with a specified suffix.

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 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 regular expression as inputs, and returns an array of all matches found using the String.matchAll() method.

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

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

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

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

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

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

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

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

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

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

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

Create a function that repeats a given string n times.

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

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

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

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

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

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

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

Converts a given date to a time string

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 returns the nth number in the Fibonacci sequence using recursion.

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

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

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

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

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 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 year using Date's built-in getFullYear method

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

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.

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 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.

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

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

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

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

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.

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

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

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

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

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 sorts an array of strings in alphabetical order using String.prototype.localeCompare()

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

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.

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 all its substrings of length 3 or greater. You must use String.prototype.slice() to achieve this.

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

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.

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

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.

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.

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

Write a function that accepts a date object and a number of seconds (0 - 59) and returns a new date object with the seconds set to the provided value. The operation should be done using the setUTCSeconds() 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 returns the current minutes.