w3resource

JavaScript: Check a number is prime or not

JavaScript Function: Exercise-8 with Solution

Write a JavaScript function that accepts a number as a parameter and check the number is prime or not.

Note : A prime number (or a prime) is a natural number greater than 1 that has no positive divisors other than 1 and itself.

Pictorial Presentation:

JavaScript: Check a number is prime or not

Sample Solution: -

HTML Code:

<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Check a number is prime or not</title>
</head>
<body>
 
</body>
</html>

JavaScript Code:

function test_prime(n)
{

  if (n===1)
  {
    return false;
  }
  else if(n === 2)
  {
    return true;
  }else
  {
    for(var x = 2; x < n; x++)
    {
      if(n % x === 0)
      {
        return false;
      }
    }
    return true;  
  }
}

console.log(test_prime(37));

Sample Output:

true

Flowchart:

Flowchart: JavaScript function: Check a number is prime or not

Live Demo:

See the Pen JavaScript -Counts the number of vowels within a string-function-ex- 7 by w3resource (@w3resource) on CodePen.


Improve this sample solution and post your code through Disqus

Previous: Write a JavaScript function that accepts a string as a parameter and counts the number of vowels within the string.
Next: Write a JavaScript function which accepts an argument and returns the type.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.



Follow us on Facebook and Twitter for latest update.

JavaScript: Tips of the Day

Shorten an array using its length property

A great way of shortening an array is by redefining its length property.

let array = [0, 1, 2, 3, 4, 5, 6, 6, 8, 9]
array.length = 4
// Result: [0, 1, 2, 3]

Important to know though is that this is a destructive way of changing the array. This means you lose all the other values that used to be in the array.

Ref: https://bit.ly/2LBj213