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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.

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

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

Create a function that accepts a Set and a value to remove, and returns the updated Set after deleting the value.

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

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

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

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

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

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

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

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

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

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

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

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.

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

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

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

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

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

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.

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 as input and returns the string in all lowercase letters.

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.

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

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

Create a function that takes a year (YYYY) and returns the date object with its year set to the provided year.

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().

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

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

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

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

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

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

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

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

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

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

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

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 uses the copyWithin method to replace specified elements within an array.

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 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.

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

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 takes an array as input and returns a new array with the elements in reversed order.

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

Create a function that takes an array and reverse its order in place.

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 returns an array of char codes from a string

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

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

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

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

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

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

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

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

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.

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 returns it in lowercase using the toLocaleLowerCase() method.

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

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

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

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

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

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.

Given an array of numbers, use reduce method to obtain a single value that represents the sum of all numbers in the array.

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

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

Implement a function that uses String.prototype.trimEnd() to trim whitespace at the end of a string.

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

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

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

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

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

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

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

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 returns the result of a string match with a given pattern.

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.

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.

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

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

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

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