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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.

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

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

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

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

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

Write a function that takes a string and returns all its substrings of length 3 or greater. You must use String.prototype.slice() to achieve this.

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

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

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

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

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

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.

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.

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

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

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

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

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

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

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

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

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

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

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 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.

Implement normalize method to format a string removing all the accents

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

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 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.

Convert a string to an array of Unicode code points using String.prototype.codePointAt() 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 checks if a given variable is an array. If it is an array, return true, otherwise return false.

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 sets the UTC month of a given date object.

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

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 replaces all instances of a specified substring in a given string.

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

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

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

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

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

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.

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

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

Create a function that replaces all occurrences of a substring with a new 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 number as parameters. The function should return the string repeated `n` times, where n is the number passed as parameter.

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

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 takes in two parameters, a string and a substring, and checks if the string includes the substring. Return a boolean value.

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

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

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.

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.

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

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

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

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

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

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

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

Implement a function that concatenates a given string 'n' times using the String.prototype.repeat() 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 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 a number representing the desired month, and sets the month of the date to the given month.

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

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

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

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 to search for a substring in a given string using String.prototype.search() 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 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 a string as input and returns the string in all lowercase letters.

Given an array of numbers, use reduce method to obtain a single value that represents the sum of all numbers in the array.

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

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

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

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

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

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

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

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

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

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

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

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