How to implement a PHP class to calculate the factorial of an integer? (detailed code explanation)

This article mainly introduces you to implement a PHP class to calculate the factorial of integers.

Recommended reference study: "PHP Tutorial"

First of all, let’s briefly understand what factorial is?

The factorial of a positive integer is the product of all positive integers less than and equal to the number, and the factorial of 0 is 1. The factorial of a natural number n is written n!.

To put it simply, for example, the factorial of 6 is 6!=1*2*3*4*5*6

So how do we implement the PHP class to calculate integers? of factorial?

The implementation code is as follows:

_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();
?>

The above code is to calculate the factorial of 5, and the output result is 120.

Related function introduction:

is_int() functionDetects whether the variable is an integer.

__construct() function Creates a new SimpleXMLElement object. PHP 5 allows developers to define a method as a constructor in a class. Classes with a constructor will call this method every time a new object is created, so it is very suitable for doing some initialization work before using the object.

We can use a logic diagram to represent it:

This article introduces the method of implementing a PHP class to calculate integer factorials, which has a certain reference Value, I hope it will be helpful to friends in need!

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