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

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

Sort an array of words based on their alphabetical order using String.prototype.localeCompare() method.

Write a function that finds the last index of a given element in an array using the Array.prototype.findLastIndex method.

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

Create a function that uses the copyWithin method to replace specified elements within an array.

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

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 normalizes a string using String.prototype.normalize 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 regular expression as inputs, and returns an array of all matches found using the String.matchAll() method.

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

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

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.

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

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

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.

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.

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 returns the current year using Date's built-in getFullYear method

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

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

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 determines if two strings are anagrams of each other.

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 returns an array of values of an array using the Array.prototype.values() method.

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

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

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 repeats a given string n times.

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

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

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.

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

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 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 a value as arguments and adds the value to the beginning of the array using the unshift() method.

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

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 checks if a given string ends with a specified suffix.

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.

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

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

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

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

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.

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 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().

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

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.

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

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

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 a function that removes leading and trailing whitespace from a string using the String.prototype.trim() 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 returns an array of matched patterns using String.prototype.matchAll().

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

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

Write a function that replaces the first occurrence of a specific string in a given string.

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

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

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

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

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

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

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

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

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.

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

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

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

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

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.

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

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

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

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

Implement normalize method to format a string removing all the accents

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

Create a function to search for a substring in a given string using String.prototype.search() 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 returns the character at the specified index of a given string.

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

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 returns the current minutes.

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

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

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

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

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

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

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

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.