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

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

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

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

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

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

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

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

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

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

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 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.

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.

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

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

Create a function that returns the current date as a number (1-31).

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

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.

Implement a function that replaces all instances of a specified substring in a given 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 flattens nested arrays using Array.prototype.flat() method.

Write a function that checks if a given string includes a specific substring. Use String.prototype.includes() 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 date and a year and sets the date's UTC full year 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 uses the String.prototype.lastIndexOf() method to find the index of the last occurrence of a specified substring in a given string.

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 two arrays as arguments and concatenates them into a new array using the Array.prototype.concat() method.

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 sorts an array of strings in alphabetical order using String.prototype.localeCompare()

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 regular expression and returns an array of all the substrings in the string that match the regular expression.

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

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

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

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

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

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

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

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

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

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')

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

Create a function that uses the String.prototype.replaceAll() method to replace all occurrences of a given substring within a string.

Write a function that returns an array of char codes from a 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().

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 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.

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

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

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

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

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

Given a date, return the UTC date.

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

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

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

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

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

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.

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

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

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 receives a string and normalizes it using the String.prototype.normalize() method. Apply the NFC normalization form.

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 replaces the first occurrence of a specific string in a given string.

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

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

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

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

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 all its substrings of length 3 or greater. You must use String.prototype.slice() to achieve this.

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

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

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

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

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 returns the current minutes.

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 replaces all occurrences of a substring with a new string.

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

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 takes an array and reverse its order in place.

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 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 checks if a given string ends with a specified suffix.

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 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.