Library

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

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

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

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

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

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

Create a function that takes a string as input and returns the string in all lowercase letters.

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.

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.

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

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

Write a function that flattens nested arrays using Array.prototype.flat() 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.

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

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.

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

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

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()

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 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.

In this kata, you will be working with the String.prototype.toLocaleUpperCase() method to convert a string to uppercase according to the user's locale.

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

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 an array and reverse its order in place.

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

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

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

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.

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

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.

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.

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

Implement normalize method to format a string removing all the accents

Create a function that returns the current year using Date's built-in getFullYear 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 replaces all instances of a given substring with another string within a larger string using String.prototype.replaceAll() method.

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.

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

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

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

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

Converts a given date to a time 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 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.

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.

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 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 sets the UTC month of a given date object.

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

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

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

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

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

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

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

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

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

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

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 variable is an array. If it is an array, return true, otherwise return false.

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

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

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 returns it in lowercase using the toLocaleLowerCase() method.

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 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.

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

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

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

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

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

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

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

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

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

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

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

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 replaces all occurrences of a substring with a new string.

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

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 string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

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

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

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

Write a function that takes a date and returns the year in the hh:mm:ss format.

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

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 concatenates two strings using the String.prototype.concat() method. The function should take two string parameters and return the concatenated string.

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