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

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.

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.

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

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 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.

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

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

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

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

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 returns an array of values of an array using the Array.prototype.values() method.

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

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

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

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

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

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

Create a function that takes an array and reverse its order in place.

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.

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

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

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

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 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 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 sets the UTC month of a given date object.

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

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 a new array with the elements in reversed order.

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 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.

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

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

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

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.

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

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

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

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

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

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

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

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

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.

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

Converts a given date to a time string

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 n, the function should return the string repeated n times.

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.

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

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

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.

Write a function that can take in a list of numbers and precision cut them to a desired number of decimal places.

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

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

Write a function that takes a string and returns an array of code points for each character in the string using String.prototype.codePointAt() method.

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().

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 various functionalities using Array.prototype.slice() method

Create a function that repeats a given string n times.

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 string in all lowercase letters.

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

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

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

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

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

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.

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

Create a function that returns the current minutes.

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

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.

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

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.

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

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

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

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

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 object and returns the date formatted in the user's local format using the toLocaleDateString() method.

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

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

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

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