PHP Class Exercises : Calculate the factorial of an integer

PHP class: Exercise-3 with Solution

Write a PHP class that calculates the factorial of an integer.

Sample Solution:

PHP Code:

class factorial_of_a_number
  protected $_n;
  public function __construct($n)
     if (!is_int($n))
	      throw new InvalidArgumentException('Not a number or missing argument');
    $this->_n = $n;
  public function result()
     $factorial = 1;
     for ($i = 1; $i <= $this->_n; $i++)
	    $factorial *= $i;
	   return $factorial;

$newfactorial = New factorial_of_a_number(5);
echo $newfactorial->result();

Sample Output:


Flowchart :

Flowchart: Calculate the factorial of an integer

PHP Code Editor:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Write a simple PHP class which displays an introductory message like "Hello All, I am Scott", where "Scott" is an argument value of the method within the class.
Next: Write a PHP class that sorts an ordered integer array with the help of sort() function.

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.