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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 converts a given string to uppercase

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

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.

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 uses the String.prototype.replaceAll() method to replace all occurrences of a given substring within a string.

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

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

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 loops through a Set using Set.prototype.forEach() method and returns an array containing the results of applying the provided function to each element.

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.

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

Write 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().

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 object and returns a JSON string of the date in ISO format.

Create a function that repeats a given string n times.

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 a string and returns it in lowercase using the toLocaleLowerCase() method.

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

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

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

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

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.

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

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

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.

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.

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

Complete the functions provided to properly utilize the Date.now() 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 returns an array of char codes from a 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.

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

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.

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

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

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

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

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

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

Given a date, return the UTC date.

Implement various functionalities using Array.prototype.slice() method

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

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.

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

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

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

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

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

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

Create a function that returns an array of values of an array using the Array.prototype.values() method.

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

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

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

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

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

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

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

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

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 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().

Write a function that flattens nested arrays using Array.prototype.flat() method.

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

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

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

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

Write a function that takes a string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

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

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

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

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

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.

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

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

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

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

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 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.

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

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

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

Write a function that takes a Set object as a parameter and returns an array of keys using Set.prototype.keys().

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