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We are given an array of n entries, of which only 2 are Numbers, all other entries are null. Something like this: const arr = [null, null, -1, null, null, null, -3, null, null, null]; We are supposed to write a function that takes in this array and complete the arithmetic series of which these two numbers are a part. To understand this problem more clearly, we can think of these null values as blank space where we need to fill numbers so that the whole array forms an arithmetic progression. About Arithmetic Progression ... Read More
To cut a string after X characters in JavaScript, you can use several methods. The most common approaches are substr(), substring(), and slice(). Using substr() Method The substr() method extracts a portion of a string, starting at a specified index and extending for a given number of characters. var myName = "JohnSmithMITUS"; console.log("The String = " + myName); var afterXCharacter = myName.substr(0, 9); console.log("After cutting the characters the string = " + afterXCharacter); The String = JohnSmithMITUS After cutting the characters the string = JohnSmith Using substring() Method The substring() ... Read More
To create a button that increments a value by 10 each time it's clicked, you can use JavaScript's click() event listener along with parseInt() to handle numeric operations. Basic Approach The core concept involves storing a counter variable, adding 10 to it on each button click, and updating the display element with the new value. Example Increment by 10 10 0 ... Read More
We have a string of length m that contains first m letters of the English alphabets, but somehow, one element went missing from the string. So, now the string contains, m-1 letters We are required to write a function that takes in one such string and returns the missing element from the string. Example Following is the code − const str = "acdghfbekj"; const missingCharacter = str => { // to make the function more consistent const s = str.toLowerCase(); ... Read More
To customize the position of an alert box, you need to create a custom alert since the native JavaScript alert() function cannot be positioned. We can build a custom alert box using HTML, CSS, and JavaScript, then control its position using CSS properties like top and left. Creating a Custom Alert Box The native alert() box position is controlled by the browser and cannot be customized. Instead, we create a custom modal dialog that mimics an alert box behavior. Example: Custom Positioned Alert Here's how to create a custom alert box with customizable positioning: ... Read More
This tutorial shows different ways to get the number of options in a dropdown list using JavaScript. When working with HTML forms, you may need to count dropdown options for validation or dynamic functionality. A dropdown list is created using the tag with multiple elements. JavaScript provides several methods to count these options programmatically. Using options.length Property The most straightforward method is accessing the options.length property of a select element. First, get the select element by its ID, then use the options.length property. Syntax var selectElement = document.getElementById("dropdown"); var optionCount = selectElement.options.length; ... Read More
The border-right-style property in CSS sets the line style of an element's right border. It determines how the right border appears, whether solid, dashed, dotted, or other styles. Syntax border-right-style: none | hidden | dotted | dashed | solid | double | groove | ridge | inset | outset; Property Values Value Description none No border (default) solid Single solid line dashed Series of dashes dotted Series of dots double Two solid lines groove 3D grooved appearance ridge ... Read More
Multi-dimensional arrays in JavaScript are arrays that contain other arrays as elements. They're useful when you need to organize data in rows and columns, like storing temperatures for each day of the week at different time intervals. Creating Multi-Dimensional Arrays Instead of creating separate arrays for each day: let monday = [35, 28, 29, 31]; let tuesday = [33, 24, 25, 29]; console.log("Monday temperatures:", monday); console.log("Tuesday temperatures:", tuesday); Monday temperatures: [ 35, 28, 29, 31 ] Tuesday temperatures: [ 33, 24, 25, 29 ] You can use a multi-dimensional array to ... Read More
In JavaScript, you can format objects into arrays using various methods like destructuring, Object.keys(), Object.values(), or custom formatting based on your needs. This is useful for data transformation and display purposes. Example: Formatting Object Properties to Array Format Object to Array body { font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif; ... Read More
When working with arrays of data, you often need to group and sum values based on a common key. This article demonstrates how to sum array values with similar keys using JavaScript's reduce() method. Let's say we have an array containing stock transaction data for a company over time: const transactions = [ ['AAPL', 'buy', 100], ['WMT', 'sell', 75], ['MCD', 'buy', 125], ['GOOG', 'sell', 10], ['AAPL', 'buy', 100], ['AAPL', 'sell', 100], ... Read More