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

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 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.

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 a string as input and returns the same string in uppercase letters using the `toString()` method of the String object.

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

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 removes all unused items in a Set collection

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

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

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

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

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

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

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

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

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.

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 in an array of music tracks and returns an object with the count of each genre in the array

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

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

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

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

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

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

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

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

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

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

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 normalizes a string using String.prototype.normalize 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.

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

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

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

Create a function that takes two parameters: a string and a regular expression. The function should return an array of all matches found in the string using the regular expression.

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.

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.

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 program that classifies music genres based on certain audio features

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

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

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

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.

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.

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

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

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.

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.

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

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

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

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

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

Implement a function that removes leading and trailing whitespace from a string using the String.prototype.trim() method.

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

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

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

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 sorts an array of strings in alphabetical order using String.prototype.localeCompare()

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

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 a date and a year as arguments and returns a new date with the year set to the specified value using Date.prototype.setFullYear().

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

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

Given a date, return the UTC date.

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

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

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

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')

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

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

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

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 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 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 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().

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

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

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

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

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.

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

Implement normalize method to format a string removing all the accents

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

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

Write a function that takes an array of numbers and returns their sum, using Array.prototype.reduceRight().

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

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

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

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