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

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

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

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 normalize method to format a string removing all the accents

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

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

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

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()

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

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.

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

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

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

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

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.

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

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 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.

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

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

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.

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

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.

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

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

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

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

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

Converts a given date to a time string

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().

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

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

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

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.

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

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

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

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

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

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.

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

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

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 and regular expression as inputs, and returns an array of all matches found using the String.matchAll() method.

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

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

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

Create a function that will return an array in a localized way using the toLocaleString 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 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 same string in uppercase letters using the `toString()` method of the String object.

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

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

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

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

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.

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

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 normalizes it using the String.prototype.normalize() method. Apply the NFC normalization form.

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

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

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

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.

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

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

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

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

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

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

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

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.

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.

Write a function that takes a date and returns the year in the hh:mm:ss 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 converts a given string to its string representation using the toString() method.

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

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

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

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

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.

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

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

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

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

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.

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