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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().

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.

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.

Write a function that takes two arrays as arguments and concatenates them into a new array using the Array.prototype.concat() method.

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

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

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

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 an array of numbers and returns their sum, using Array.prototype.reduceRight().

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

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

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

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

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

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 a function that removes all unused items in a Set collection

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 an array as input and returns an array of the keys of the given array using Array.prototype.keys() method.

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

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

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

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 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 repeats a given string n times.

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

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.

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

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

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

Create a function that returns the current minutes.

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.

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

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

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

Write a function that takes a date string as input and converts it to a UTC date string format.

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

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

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

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

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

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

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 replaces all instances of a given substring with another string within a larger string using String.prototype.replaceAll() method.

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

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 returns it in lowercase using the toLocaleLowerCase() method.

Converts a given date to a time string

Write a function that takes a string and returns an array of matched patterns using String.prototype.matchAll().

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

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 date object and a number of seconds (0 - 59) and returns a new date object with the seconds set to the provided value. The operation should be done using the setUTCSeconds() 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 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 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 checks if a given string ends with a specified suffix.

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

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.

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

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

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

Write a function that returns a substring of a given string, starting at a specified index and ending before a specified index.

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

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.

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

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

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

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

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

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

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

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

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

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

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

Implement a function that groups the elements of an array based on a given predicate function.

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

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

Create a function that returns the current year using Date's built-in getFullYear 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 takes an array and a value and pushes the value to the end of the array using Array.prototype.push().

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

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

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

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.

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.

Write a function that converts a given string to its string representation using the toString() 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 flattens nested arrays using Array.prototype.flat() method.