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

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 converts a given string to uppercase

Given a date, return the UTC date.

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

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

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

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

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.

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

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

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

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

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

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

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.

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 date and a year as arguments and returns a new date with the year set to the specified value using Date.prototype.setFullYear().

Implement normalize method to format a string removing all the accents

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

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.

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

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

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

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

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.

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

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

Write a function that checks if a given variable is an array. If it is an array, return true, otherwise return false.

Implement the Array.prototype.with() method that returns a new array with the elements from the original array and the added elements.

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 replaces the first occurrence of a specific string in a given string.

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

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.

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

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.

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

Create a function that takes a Date object and returns a JSON string of the date in ISO format.

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

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

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.

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

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

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 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.

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

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.

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

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 uses the copyWithin method to replace specified elements within an array.

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

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.

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

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

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 the String.prototype.lastIndexOf() method to find the index of the last occurrence of a specified substring in a given string.

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

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

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 and a number, and repeats the string the given number of times.

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

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.

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

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

Create a function that takes a string and returns an array of the char codes for each character in the string

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

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

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

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

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

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

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 of numbers and returns the index of a given element. Use Array.prototype.findIndex() to implement the function.

Write a function that takes an array and a value and pushes the value to the end of the array using Array.prototype.push().

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

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().

Create a function that checks if a given string ends with a specified suffix.

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

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

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

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

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

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

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

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.

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

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 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 returns true if a given string starts with a specific substring.