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

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

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

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

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

Given a sentence, split it into an array of words using the String.prototype.split() 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 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 returns the current year using Date's built-in getFullYear method

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.

Implement various functionalities using Array.prototype.slice() 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

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.

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

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 determines if two strings are anagrams of each other.

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

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

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

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

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

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

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.

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 replaces the first occurrence of a specific string in a given string.

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 takes a string as input and returns the same string in uppercase letters using the `toString()` method of the String object.

Given a date, return the UTC date.

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

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

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 checks if all elements from an array are included in a given Set using the built-in Set.prototype.has() method.

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

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

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

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

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.

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

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

Implement a function that uses String.prototype.trimEnd() to trim whitespace at the end of a 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 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 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 a year (YYYY) and returns the date object with its year set to the provided year.

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

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

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

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

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.

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.

Converts a given date to a time string

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

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 returns an array of char codes from a string

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

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.

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

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.

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

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

Implement normalize method to format a string removing all the accents

Write a function that returns the result of a string match with a given pattern.

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

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

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 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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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 concatenates two strings using the String.prototype.concat() method. The function should take two string parameters and return the concatenated string.

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

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

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

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

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