Library

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

Converts a given date to a time string

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

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

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.

Write a function that concatenates two strings using the String.prototype.concat() 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 takes a string and returns an array of the char codes for each character in the string

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 returns an array of char codes from a string

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

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

Write a function that checks if a given string includes a specific substring. Use String.prototype.includes() 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 returns whether a given string ends with the provided suffix or not

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

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

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')

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

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.

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

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

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

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.

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

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

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.

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.

Implement normalize method to format a string removing all the accents

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

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

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

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

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

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

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 if every element in an array satisfies a given condition.

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

Given a date, return the UTC date.

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 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.

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

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.

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

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

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

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

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.

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

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.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.

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

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

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

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.

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

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

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.

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.

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

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

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 takes a date object and a number representing the desired month, and sets the month of the date to the given month.

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

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

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

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

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 takes a string and returns an array of matched patterns using String.prototype.matchAll().

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().