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

Given a date, return the UTC date.

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

Converts a given date to a time string

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

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

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.

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.

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 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.

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.

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

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 as arguments, and finds the last occurrence of the substring in the string. If the substring is not found, return -1.

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

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

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

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

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

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

Write a function that takes a Set object as a parameter and returns an array of keys using Set.prototype.keys().

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

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

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

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

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

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

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 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 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 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 returns the current month from Date object using Date.prototype.getMonth()

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

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

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

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().

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

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

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 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 replaces all occurrences of a substring with a new string.

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

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

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.

Implement normalize method to format a string removing all the accents

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.

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

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

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

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

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 checks if a given string ends with a specified suffix.

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

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

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

Write a function that converts a given string to uppercase

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 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.

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

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

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 repeats a given string n times.

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 an algorithm that manages the overbooking of an airline flight.

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

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

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.

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

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

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

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

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.

Create a function that takes a string and a number and pads that string with a specified character until it reaches the given length.

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

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 the current minutes.

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

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 and returns the year in the hh:mm:ss format.

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

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 returns the index of the first occurrence of a given element in an array using Array.prototype.indexOf(). If the element is not found in the array, return -1.

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.

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.

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

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

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

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

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

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

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

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