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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.

Given a date, return the UTC date.

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

Implement normalize method to format a string removing all the accents

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

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

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

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

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 same string in uppercase letters using the `toString()` method of the String object.

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

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

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

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

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

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 program that classifies music genres based on certain audio features

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

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.

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

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

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

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

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

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

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

Create a function that takes in an array of music tracks and returns an object with the count of each genre in the array

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

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

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

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

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

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 returns the character at the specified index of a given string.

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

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

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

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

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

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

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

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

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

Write a function that takes a Date object and returns the date formatted in the user's local format using the toLocaleDateString() method.

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

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.

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.

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().

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

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 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 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 integer n and returns the nth Fibonacci number using recursion.

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')

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

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

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

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

Create a function that takes a string and a number and pads that string with a specified character until it reaches the given length.

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.

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

Write a function that takes a string and returns it in lowercase using the toLocaleLowerCase() method.

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

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

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

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.

Converts a given date to a time string

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

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

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

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

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

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

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

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

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

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 repeats a given string n times.

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 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. The function should take two string parameters and return the concatenated string.

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().

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

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

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.

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

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