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

Write a function that converts a given string to uppercase

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.

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

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

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

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

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

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

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.

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

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.

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

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

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

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

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

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

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 takes a date object and a number representing the desired month, and sets the month of the date to the given month.

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

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

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

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

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

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

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

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

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.

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

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

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

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

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

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

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 returns all its substrings of length 3 or greater. You must use String.prototype.slice() to achieve this.

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 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 a value as arguments and adds the value to the beginning of the array using the unshift() 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 JavaScript function to find the index of an item in an array using Array.prototype.findIndex().

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.

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

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.

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

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 repeats the string the given number of times.

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

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 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 replaces all occurrences of a substring with a new string.

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.

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 returns an array of values of an array using the Array.prototype.values() method.

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

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

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

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 an Inventory Management System that allows users to add, remove and update items in the inventory.

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

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

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

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

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

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 returns the result of a string match with a given pattern.

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

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.

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 takes an array of numbers and returns the index of a given element. Use Array.prototype.findIndex() to implement the function.

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

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

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 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.

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

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

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.

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

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

Implement a function that removes all unused items in a Set collection

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

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

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.

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().

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 in a date and returns the seconds within the minute in UTC time.

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

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.