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Create a function that repeats a given string n times.

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

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

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

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

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

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

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

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 an algorithm that manages the overbooking of an airline flight.

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

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.

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

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

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

Write a function that converts a given string to uppercase

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.

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 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.

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

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

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

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

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.

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

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

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

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

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 as input and returns a new array with the elements in reversed order.

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

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.

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 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.

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

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

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

Create a function that returns the current minutes.

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

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

Write a function that returns the nth number in the Fibonacci sequence using recursion.

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

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

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

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.

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

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

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

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.

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

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

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 sets the UTC month of a given date object.

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

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

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

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

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 a date and a year as arguments and returns a new date with the year set to the specified value using Date.prototype.setFullYear().

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

Write a function that replaces the first occurrence of a specific string in a given 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.

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

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

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

Write a function that takes a Date object and returns the date formatted in the user's local format using the toLocaleDateString() 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 two strings as input and concatenates them using the String.prototype.concat() method.

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

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

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

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

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

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

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 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.

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

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

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

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

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

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

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

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