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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.

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

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

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

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

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

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

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

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

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 sorts an array of strings in alphabetical order using String.prototype.localeCompare()

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

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

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

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

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

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.

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

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.

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.

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

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.

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

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

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

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

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

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

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.

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

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

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.

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

Write a function that converts a given string to uppercase

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

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.

Write a function that checks if every element in an array satisfies a given condition.

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

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

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

Write a function that returns a substring of a given string, starting at a specified index and ending before a specified index.

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.

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

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

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

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

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 an array of Unicode code points using String.prototype.codePointAt() method.

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

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 a string and a regular expression and returns an array of all the substrings in the string that match the regular expression.

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

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.

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

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

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 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().

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

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

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

Create a function that returns the current minutes.

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.

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

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 an array of matched patterns using String.prototype.matchAll().

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

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 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 normalizes a string using String.prototype.normalize 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 returns the month of a Date object in UTC time zone.

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

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

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.

Given a date, return the UTC date.

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 the result of a string match with a given pattern.

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.

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

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

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.

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

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