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

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

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

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

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

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 the result of a string match with a given pattern.

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

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

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 takes a year (YYYY) and returns the date object with its year set to the provided year.

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

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

Write a function that converts a given string to uppercase

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

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

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.

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

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

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.

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

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

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.

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

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

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 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 takes in an array of music tracks and returns an object with the count of each genre in the array

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

Create a function that repeats a given string n times.

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

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 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.

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

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

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 program that classifies music genres based on certain audio features

This kata focuses on using String.prototype.indexOf() 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 normalizes it using the String.prototype.normalize() method. Apply the NFC normalization form.

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

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

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

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

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

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

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

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 removes all unused items in a Set collection

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

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

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

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

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

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.

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

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

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 n, the function should return the string repeated n times.

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

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

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

Convert a string to an array of Unicode code points using String.prototype.codePointAt() 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 takes a Date object and returns the date formatted in the user's local format using the toLocaleDateString() method.

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

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 takes an array and removes a portion of the array, as specified by the arguments, and returns the removed portion.

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

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

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

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

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 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 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().

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.

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

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

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.

Converts a given date to a time string

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

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 two parameters, a string and a substring, and checks if the string includes the substring. Return a boolean value.

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.

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