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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.

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 integer n and returns the nth Fibonacci number using recursion.

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

Convert a string to an array of Unicode code points using 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.

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

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

Create a function that repeats a given string n times.

Write a function that takes a string and returns it in lowercase using the toLocaleLowerCase() method.

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

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

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

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

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

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

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

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

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

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

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

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

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.

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 as input and returns the same string in uppercase letters using the `toString()` method of the String object.

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

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 flattens nested arrays using Array.prototype.flat() 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 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 and reverse its order in place.

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

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

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 greets the user depending on the current hour of the day.

Converts a given date to a time string

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

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

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

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

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

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

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

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.

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.

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 program that classifies music genres based on certain audio features

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

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.

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

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

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

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

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

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

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

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

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')

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.

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

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.

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

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 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.

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

Create a function that takes in an array of music tracks and returns an object with the count of each genre in the array

Write a function that converts a given string to uppercase

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 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.

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

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

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

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

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.

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

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

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

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

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

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 checks if a given string has a unicode character code point greater than or equal to 128. Use the String.prototype.codePointAt() method.

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

Write a function that takes a string and a search term and returns the index of the first occurrence of the search term in the given string. If the search term is not present in the string, return -1.

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 a string as input and returns the string in all lowercase letters.

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

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.

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

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