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

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

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

Create a function that returns the current minutes.

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 an array and reverse its order in place.

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

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

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

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

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

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

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

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

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

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.

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

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.

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

Write a function that converts a given string to uppercase

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

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 objects, group the objects based on a specific key and return a map object.

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.

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

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

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

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

Given an array of numbers and a start index, remove a certain number of elements from the array and replace them with new elements.

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 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 whether a given string ends with the specified suffix or not.

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

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

Converts a given date to a time string

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

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().

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

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()

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

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

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

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

Create a function that normalizes a string using String.prototype.normalize 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 replaces all instances of a given substring with another string within a larger string using String.prototype.replaceAll() method.

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

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.

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

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

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

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

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

Write a function that takes an array and a value and pushes the value to the end of the array using Array.prototype.push().

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

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.

Combine two arrays into a single array using the Array.prototype.concat() method

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

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.

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

Write a function that takes two arrays as arguments and concatenates them into a new array using the Array.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 takes a Date object and returns the date formatted in the user's local format using the toLocaleDateString() method.

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

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

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

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.

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

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

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

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

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 flattens nested arrays using Array.prototype.flat() method.

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 a string and returns an array of the char codes for each character in the string

Create a function that uses the copyWithin method to replace specified elements within an array.

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 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 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 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 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.

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

Write a function that checks if an element is present in an array using Array.prototype.includes() method.

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

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

Given a date, return the UTC date.

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

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