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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.

Create a function that returns the current minutes.

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 counts the number of seconds in a given timestamp

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

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

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

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

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

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

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

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

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

Write a function that converts a given string to uppercase

Implement normalize method to format a string removing all the accents

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

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 takes an array as input and returns an array of the keys of the given array using Array.prototype.keys() method.

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

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

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

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

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

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

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

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.

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

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 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.

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

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

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

Create a function that repeats a given string n times.

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

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

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

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

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

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 returns true if a given string starts with a specific substring.

Write a function that normalizes a string using String.prototype.normalize().

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.

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

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

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.

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

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

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

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

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

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

Write a function that takes two arrays as arguments and concatenates them into a new array using the Array.prototype.concat() method.

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

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

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

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.

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.

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 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.

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

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

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

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 a date string as input and converts it to a UTC date string format.

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

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 finds the last index of a given element in an array using the Array.prototype.findLastIndex method.

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

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

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 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.

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

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

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

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

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

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 takes an array and reverse its order in place.

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

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

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

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

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

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

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 returns the value of a given string using the String.prototype.valueOf() 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.

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

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