Library

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

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

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

Create a function that searches for the last index of a substring in an array using Array.prototype.lastIndexOf().

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

Converts a given date to a time 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.

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

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

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

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

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

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

Create a function that returns an array of values of an array using the Array.prototype.values() 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 function that takes an array as input and returns an array of the keys of the given array using Array.prototype.keys() method.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.

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

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

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

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

Given a date, return the UTC date.

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

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

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

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

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

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

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

Implement normalize method to format a string removing all the accents

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

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.

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

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

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

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

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

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

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

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.

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

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

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 an array of numbers and returns their sum, using Array.prototype.reduceRight().

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')

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

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.

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

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

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

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

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

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

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

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