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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.

Implement a function that concatenates a given string 'n' times using the String.prototype.repeat() 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 checks if a given string includes a specific substring. Use String.prototype.includes() method.

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

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

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

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 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.

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.

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

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 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 a new array with the elements in reversed order.

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

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

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

Given a date, return the UTC date.

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

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

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

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

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

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.

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

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

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

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

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

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.

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

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

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

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

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

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 receives a Date object and returns the milliseconds that have elapsed since the start of the day.

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

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

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.

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 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 a substring of a given string, starting at a specified index and ending before a specified index.

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

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

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

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 determines if two strings are anagrams of each other.

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

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

Create a function that takes a year (YYYY) and returns the date object with its year set to the provided year.

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

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

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.

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

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

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

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

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

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

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

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

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

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

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.