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

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

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.

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

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

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

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

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

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.

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

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

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.

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

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 in an array of music tracks and returns an object with the count of each genre in the array

Create a function that repeats a given string n times.

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().

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

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

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

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

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.

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

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

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.

Create a function that returns the current minutes.

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

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

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

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

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

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

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

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

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.

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 will return an array in a localized way using the toLocaleString 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 returns the nth number in the Fibonacci sequence using recursion.

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.

Converts a given date to a time string

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

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

Write a function that takes a string and returns it in lowercase using the toLocaleLowerCase() method.

Given a date, return the UTC date.

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

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

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.

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

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

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.

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

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

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

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

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

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

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.

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

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

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

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

Implement normalize method to format a string removing all the accents

Write a function that takes two arrays as arguments and concatenates them into a new array using the Array.prototype.concat() 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 a string and returns an array of the char codes for each character in the string

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 returns the current year using Date's built-in getFullYear method

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

Write a function that takes a date object and a number of seconds and returns a new date object with the seconds set to the provided value. Example input: setSeconds(new Date('2022-10-10T10:10:10'), 30) Expected output: new Date('2022-10-10T10:10:30')

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

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

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 replaces all occurrences of a substring with a new string.

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

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

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

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

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

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 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.

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

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

Given an array of numbers and a start index, remove a certain number of elements from the array and replace them with new elements.

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

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

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

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

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

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