w3resource

JavaScript: Get the difference between a given number

JavaScript Basic: Exercise-15 with Solution

Write a JavaScript program to get the difference between a given number and 13, if the number is greater than 13 return double the absolute difference.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>The difference between a given number and 13, if the number is greater than 13 return double the absolute difference.</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function difference(n)
 {
    if (n <= 13)
        return 13 - n;
    else
        return (n - 13) * 2;
 }
console.log(difference(32))
console.log(difference(11))

Sample Output:

38
2

ES6 Version:

function difference(n)
 {
    if (n <= 13)
        return 13 - n;
    else
        return (n - 13) * 2;
 }
console.log(difference(32))
console.log(difference(11))

Live Demo:

See the Pen JavaScript: Number difference - basic-ex-15 by w3resource (@w3resource) on CodePen.


Improve this sample solution and post your code through Disqus

Previous: Write a JavaScript exercise to get the extension of a filename.
Next: Write a JavaScript program to compute the sum of the two given integers.

What is the difficulty level of this exercise?



JavaScript: Tips of the Day

Promise object

const myPromise = () => Promise.resolve('I have resolved!');

function firstFunction() {
  myPromise().then(res => console.log(res));
  console.log('second');
}

async function secondFunction() {
  console.log(await myPromise());
  console.log('second');
}

firstFunction();
secondFunction();

With a promise, we basically say I want to execute this function, but I'll put it aside for now while it's running since this might take a while. Only when a certain value is resolved (or rejected), and when the call stack is empty, I want to use this value.
We can get this value with both .then and the await keyword in an async function. Although we can get a promise's value with both .then and await, they work a bit differently.
In the firstFunction, we (sort of) put the myPromise function aside while it was running, but continued running the other code, which is console.log('second') in this case. Then, the function resolved with the string I have resolved, which then got logged after it saw that the callstack was empty.
With the await keyword in secondFunction, we literally pause the execution of an async function until the value has been resolved before moving to the next line.
This means that it waited for the myPromise to resolve with the value I have resolved, and only once that happened, we moved to the next line: second got logged.

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