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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.

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

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

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

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

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

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

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 returns the value of a given string using the String.prototype.valueOf() 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 determines if two strings are anagrams of each other.

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

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

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.

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

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

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 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.

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.

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

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.

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

Write a function that takes a string and returns it in lowercase using the toLocaleLowerCase() method.

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 replaces all occurrences of a substring with a new string.

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.

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

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

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.

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

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

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

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

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

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

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

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 sets the UTC month of a given date object.

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

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

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 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 returns an array of char codes from a string

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

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

Create a function that repeats a given string n times.

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 checks if a given string ends with a specified suffix.

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

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

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

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

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

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.

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

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

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

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

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

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

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

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

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

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.

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

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

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

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

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

Create a function that takes in an array of music tracks and returns an object with the count of each genre in the array

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

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

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 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.

Given a date, return the UTC date.

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

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

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

Implement a function that takes in a Set and returns an array of entries

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

Write a function that converts a given string to uppercase

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

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 returns the current minutes.

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.

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