PHP Challenges: Check whether a given number is an ugly number

PHP Challenges - 1: Exercise-19 with Solution

Write a PHP program to check whether a given number is an ugly number.

Input : 12

Ugly numbers are positive numbers whose only prime factors are 2, 3 or 5. The sequence 1, 2, 3, 4, 5, 6, 8, 9, 10, 12, ...
shows the first 10 ugly numbers.
Note: 1 is typically treated as an ugly number.

Explanation :

Sample Solution :

PHP Code :

<?php
function is_ugly($num)
  {
     $z = $num;
     if ($num == 0)
       {
            return "$num is not an Ugly number";
       }
       
       $x = array(2, 3, 5);
      foreach ($x as $i)
      {
            while ($num % $i == 0)
            {
                $num /= $i;
                 }
         }         
       if ($num==1)
         {
              return "$z is an Ugly number";
         }
         else
         {
              return "$z is not an Ugly number";
         }

 }    

print(is_ugly(12)."\n");
print(is_ugly(7)."\n");
?>

Sample Output:

12 is an Ugly number                                        
7 is not an Ugly number 

Flowchart:

PHP Code Editor:

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