Library

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

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

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

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 returns an array of code points for each character in the string using String.prototype.codePointAt() 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.

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

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.

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 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().

Converts a given date to a time string

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

Create a function that returns the current minutes.

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

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

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

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

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

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

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.

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

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

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

Write a function that uses the Date.prototype.getDay() method to determine the day of the week for a given date object.

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

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

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 receives a Date object and returns the milliseconds that have elapsed since the start of the day.

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 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 and a number, and repeats the string the given number of times.

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 checks if an element is present in an array using Array.prototype.includes() 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 all unused items in a Set collection

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

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

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

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

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

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.

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

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

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

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

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

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.

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

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

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

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 replaces all instances of a specified substring in a given string.

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

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 normalizes a string using String.prototype.normalize method.

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

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

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 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.

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

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

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

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

Implement normalize method to format a string removing all the accents

Given a date, return the UTC date.

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 flattens nested arrays using Array.prototype.flat() method.

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

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 slices a string based on a given start and end indexes

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

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 and returns the year in the hh:mm:ss format.

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

Combine two arrays into a single array using the Array.prototype.concat() 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 transforms a given string to uppercase, using String.prototype.toLocaleUpperCase()

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

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

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

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

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

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

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

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 returns the current year using Date's built-in getFullYear method

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

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