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

Write a function that converts a given string to uppercase

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

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

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

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.

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

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().

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

Create a function that takes a string and a number, and repeats the string the given number of times.

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

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.

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

Given an array of person objects, sort them alphabetically by their last name 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

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

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

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

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

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

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 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 returns an array of char codes from a string

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.

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 representing the desired month, and sets the month of the date to the given month.

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

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

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

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.

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

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 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.

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

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

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 returns all its substrings of length 3 or greater. You must use String.prototype.slice() to achieve this.

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 a given variable is an array. If it is an array, return true, otherwise return false.

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

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

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 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 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.

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 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 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 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 returns an array of the char codes for each character in the string

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

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

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

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 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.

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.

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.

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

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

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

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 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.

Write a function that uses the Date.prototype.getDay() method to determine the day of the week for a given date object.

Converts a given date to a time string

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 counts the number of seconds in a given timestamp

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 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.

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

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 in a string and uses String.prototype.match() to find all occurrences of a pattern within the 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 uses the copyWithin method to replace specified elements within an array.

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 takes in a string with extra white space at the beginning and end of the string, and returns a new string with that white space removed. Use String.prototype.trim().

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.

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

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

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

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

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.

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

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

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

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

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.

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

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 takes an array and reverse its order in place.