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

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

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

Create a function that replaces all occurrences of a substring with a new string.

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

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

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().

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

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

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 sets the UTC month of a given date object.

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

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

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 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 returns the value of a given string using the String.prototype.valueOf() 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 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 uses the Date.prototype.getDay() method to determine the day of the week for a given date object.

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 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 a substring of a given string, based on the start and end index provided

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

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.

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

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 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.

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

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

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.

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

Create a function that will return an array in a localized way using the toLocaleString 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 accepts a Set and a value to remove, and returns the updated Set after deleting the value.

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

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 returns an array of char codes from a string

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

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 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.

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

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

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

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

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

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

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.

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

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

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

Create a function that repeats a given string n times.

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

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

Implement normalize method to format a string removing all the accents

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

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

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

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

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 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.

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

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

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.

Given a date, return the UTC date.

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

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.

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

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

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

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

Create a function that returns the current minutes.

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

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.

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

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

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

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

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.

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

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

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 a function that checks if all elements from an array are included in a given Set using the built-in Set.prototype.has() method.

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

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

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

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

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

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.

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