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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.

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.

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

Create a function that repeats a given string n times.

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

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

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

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

Create a function that takes a string and returns an array of the char codes for each character in the string

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

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

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

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

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

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

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 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 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.

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

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

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

Implement a function that replaces all instances of a specified substring in a given 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 returns the current date as a number (1-31).

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 two strings as input and concatenates them using the String.prototype.concat() 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.

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

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

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

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

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

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 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 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().

Given a date, return the UTC date.

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

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

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

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

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

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

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

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.

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

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

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

Create a function that takes in two parameters, a string and a substring, and checks if the string includes the substring. Return a boolean value.

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.

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.

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

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

Implement a function that returns the current month from Date object using Date.prototype.getMonth()

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 various functionalities using Array.prototype.slice() method

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

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

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

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

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

Create a function that receives a string and normalizes it using the String.prototype.normalize() method. Apply the NFC normalization form.

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

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 nth number in the Fibonacci sequence using recursion.

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

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

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.

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

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

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.

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

Implement a function that concatenates a given string 'n' times using the String.prototype.repeat() method.

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

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

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

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

Converts a given date to a time string

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

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

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

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

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

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

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

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

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.

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 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 returns the current year using Date's built-in getFullYear method