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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 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 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.

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

Create a function that repeats a given string n times.

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

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

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

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

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.

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

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.

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

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.

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

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 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 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.

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

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

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 checks if a given string ends with a specified suffix.

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.

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.

Converts a given date to a time string

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

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.

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

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

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

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

Implement normalize method to format a string removing all the accents

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

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

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

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

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

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

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.

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.

Write a function that converts a given string to uppercase

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

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

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

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

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

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

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

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

Given a date, return the UTC date.

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.

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

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

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

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.

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.

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

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

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

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

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

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

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

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.

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

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

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

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

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

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

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

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

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.

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

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

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().

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

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

Implement a function that returns the character at the specified index of a given string.

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

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

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

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

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

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

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

Write a function that normalizes a string using String.prototype.normalize().

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