Library

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.

Converts a given date to a time string

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

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

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

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

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

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

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

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.

Sort an array of words based on their alphabetical order using String.prototype.localeCompare() 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 loops through a Set using Set.prototype.forEach() method and returns an array containing the results of applying the provided function to each element.

Create a function that returns the current minutes.

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

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 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 sets the UTC month of a given date object.

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

Create a function that sorts an array of strings in alphabetical order using String.prototype.localeCompare()

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

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

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

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.

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

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

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

Given a date, return the UTC date.

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

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

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

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

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

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

Create a function that returns an array of values of an array using the Array.prototype.values() method.

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

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 concatenates two strings using the String.prototype.concat() method.

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

Implement normalize method to format a string removing all the accents

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

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

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.

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

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 various functionalities using Array.prototype.slice() 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 takes a date and returns the year in the hh:mm:ss format.

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

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

Create a function that repeats a given string n times.

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

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

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 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 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 takes in a string and uses precision cutting to remove all occurrences of the letter 'e'. Return the resulting string.

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

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

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

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 returns an array of char codes from a string

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

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

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 it in lowercase using the toLocaleLowerCase() 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.

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

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

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

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

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

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 returns true if a given string starts with a specific substring.

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

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

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

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.

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

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

Implement a function that concatenates a given string 'n' times using the String.prototype.repeat() method.

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

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

Implement the Array.prototype.with() method that returns a new array with the elements from the original array and the added elements.

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

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.

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 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.

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().

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

A kata that requires the student to use String.prototype.split() to split a given string into substrings and perform a specified operation on them.

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.