Library

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

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

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

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 string and returns an array of the char codes for each character in the string

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 greets the user depending on the current hour of the day.

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

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

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

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 that receives a string and normalizes it using the String.prototype.normalize() method. Apply the NFC normalization form.

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

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

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

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

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

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

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

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

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

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

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

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.

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.

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

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

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

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

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.

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

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

Create a function that receives a string and a number as parameters. The function should return the string repeated `n` times, where n is the number passed as parameter.

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

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

Create a function that concatenates two strings using the String.prototype.concat() 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 a string and a number and pads that string with a specified character until it reaches the given length.

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

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 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 copyWithin method to replace specified elements within an array.

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.

Converts a given date to a time string

Create a function that returns the current year using Date's built-in getFullYear 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 a string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

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

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

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

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

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

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.

Create a function that returns the current minutes.

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

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().

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

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

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

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

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

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

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

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

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

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

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

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 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.

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

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

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

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

Given an array of numbers, use reduce method to obtain a single value that represents the sum of all numbers in the array.

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

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

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

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

Create a function that replaces all occurrences of a substring with a new string.

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.

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

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

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

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 joins two arrays into a single string using Array.prototype.join() 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.

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

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

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

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.