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JavaScript - Exercises, Practice, Solution

What is JavaScript?

JavaScript is a cross-platform, object-oriented scripting language. It is a small and lightweight language. Inside a host environment ( a web browser), JavaScript can be connected to the objects of its environment to provide programmatic control over them.

JavaScript contains a standard library of objects, such as Array, Date, and Math, and a core set of language elements such as operators, control structures, and statements. Core JavaScript can be extended for a variety of purposes by supplementing it with additional objects.

The best way we learn anything is by practice and exercise questions. We have started this section for those (beginner to intermediate) who are familiar with JavaScript. Hope, these exercises help you to improve your JavaScript coding skills. Currently following sections are available, we are working hard to add more exercises. Happy Coding!

List of JavaScript Exercises :

More to Come !

Note : Since JavaScript is a loosely-typed, dynamic and expressive language, you may accomplish the same task in various ways. Therefore the ways (solution of the exercises) described here are not the only ways to do stuff. Rather, it would be great, if this helps you anyway to choose your own methods.

[ Want to contribute to JavaScript exercises? Send your code (attached with a .zip file) to us at w3resource[at]yahoo[dot]com. Please avoid copyrighted materials.]



JavaScript: Tips of the Day

JavaScript: Quick Float to Integer

If you want to convert a float to an integer, you can use Math.floor() , Math.ceil() or Math.round() . But there is also a faster way to truncate a float to an integer using |, the bitwise OR operator.

console.log(23.9 | 0);  // Result: 23
console.log(-23.9 | 0); // Result: -23

The behaviour of | varies depending on whether you're dealing with positive or negative numbers, so it's best only to use this shortcut if you're sure.
If n is positive, n | 0 effectively rounds down. If n is negative, it effectively rounds up. To put it more accurately, this operation removes whatever comes after the decimal point, truncating a float to an integer.
You can get the same rounding effect by using ~~, as above, and in fact any bitwise operator would force a float to an integer. The reasons these particular operations work is that - once forced to an integer - the value is left unchanged.

Remove Final Digits
The bitwise OR operator can also be used to remove any amount of digits from the end of an integer. This means we don't have to use code like this to convert between types:

let str = "1553"; 
Number(str.substring(0, str.length - 1));

Instead, the bitwise OR operator allows us to write:

console.log(1553 / 10   | 0)  // Result: 155
console.log(1553 / 100  | 0)  // Result: 15
console.log(1553 / 1000 | 0)  // Result: 1

Ref: https://bit.ly/3nXQk8a