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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 counts the number of seconds in a given timestamp

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

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.

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

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

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 in a date and returns the seconds within the minute in UTC time.

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

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

Create a function that takes a string as input and returns the string in all lowercase letters.

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.

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

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

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

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.

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

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

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

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

Converts a given date to a time string

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

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

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

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

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

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

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

Write a function that replaces the first occurrence of a specific string in a given 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 concatenates two strings using the String.prototype.concat() method.

Create a function that repeats a given string 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.

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

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

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

Write a function that checks if a given string includes a specific substring. Use String.prototype.includes() 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 a string and a number as arguments, and pads the string on the right side with spaces until the string reaches the desired length.

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

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

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

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

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 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().

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

Write a function that returns the value of a given string using the String.prototype.valueOf() method.

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 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.

Complete the functions provided to properly utilize the Date.now() method.

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

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

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

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

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

Implement a function that replaces all instances of a specified substring in a given string.

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

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.

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

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 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.

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

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 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.

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

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.

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

Given a date, return the UTC date.

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.

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

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 uses Array.prototype.every() to check if all the elements in an array meet a certain condition.

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

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

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

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.

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 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 returns the current month from Date object using Date.prototype.getMonth()

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

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.

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 normalizes a string using String.prototype.normalize method.

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

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

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

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

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

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.

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

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

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