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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 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 greets the user depending on the current hour of the day.

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

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 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().

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

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 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 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.

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

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

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

Implement various functionalities using Array.prototype.slice() 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 uses the Date.prototype.getDay() method to determine the day of the week for a given date object.

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

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

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

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

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

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.

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

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

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

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

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

Sort an array of words based on their alphabetical order using String.prototype.localeCompare() 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 uses the String.prototype.replaceAll() method to replace all occurrences of a given substring within a string.

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

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

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

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 as input and returns a formatted string

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

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

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

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

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 takes a string as input and returns the same string in uppercase letters using the `toString()` method of the String object.

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

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

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

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.

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

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

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.

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

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

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

Create a function that takes two strings as input and concatenates them using the String.prototype.concat() method.

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

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

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

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

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

Write a function that converts a given string to uppercase

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

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

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')

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, and repeats the string the given number of times.

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

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

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

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

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

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

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.

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

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

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.

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.

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

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

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

Create a function to search for a substring in a given string using String.prototype.search() 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 checks if a given string ends with a specified suffix.

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

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