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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 takes a Set object as a parameter and returns an array of keys using Set.prototype.keys().

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

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

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

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.

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.

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

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

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 takes an integer n and returns the nth Fibonacci number using recursion.

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.

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

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.

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

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

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

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

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

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

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.

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.

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

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

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 concatenates two strings using the String.prototype.concat() method.

Write a function that takes an array and a value as arguments and returns the index of the last occurrence of that value in the array using Array.prototype.lastIndexOf(). If the value is not found, return -1.

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

Create a function that repeats a given string n times.

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.

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

Write a function that converts a given string to uppercase

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

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

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

Create a function that takes a string and a number and pads that string with a specified character until it reaches the given length.

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

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 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 returns the current minutes.

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

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

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

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

Converts a given date to a time string

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 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 an algorithm that manages the overbooking of an airline flight.

Create a function that sets the UTC month of 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 takes a string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

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

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

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

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 returns it in lowercase using the toLocaleLowerCase() 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 checks if a given string includes a specific substring. Use String.prototype.includes() method.

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

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

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

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 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.

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

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 sentence, split it into an array of words using the String.prototype.split() 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 uses the String.prototype.trimStart() method to remove any whitespace characters from the beginning of a given string.

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

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

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

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

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

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 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().

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

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 a date and returns the year in the hh:mm:ss format.

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

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 all unused items in a Set collection

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

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

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 slices a string based on a given start and end indexes

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.

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

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

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

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.