Please note, this is a STATIC archive of website www.w3resource.com from 19 Jul 2022, cach3.com does not collect or store any user information, there is no "phishing" involved.
w3resource

PHP Challenges: Check whether an integer is the power of another integer

PHP Challenges - 1: Exercise-4 with Solution

Write a PHP program to check whether an integer is the power of another integer.

Input : 16, 2

Example: For x = 16 and y = 2 the answer is "true", and for x = 12 and y = 2 "false"

Explanation :

PHP: Check whether an integer is the power of another integer

Sample Solution :

PHP Code :

<?php
function is_Power($x, $y)
{
      $a = $x;
      $b = $y;
      while ($x % $y == 0) {
       $x = $x / $y;
     }
       
	if($x == 1)
    {
		return "$a is power of $b";
    }
    else
    {
		return "$a is not power of $b";
    }
  
}
print_r(is_Power(16,2)."\n");
print_r(is_Power(12,2)."\n");
print_r(is_Power(81,3)."\n");
?>

Sample Output: 

16 is power of 2                                            
12 is not power of 2                                        
81 is power of 3

Flowchart:

PHP Flowchart: Check whether an integer is the power of another integer

PHP Code Editor:

Contribute your code and comments through Disqus.

Previous: Write a PHP program to check whether a given positive integer is a power of four.
Next: Write a PHP program to find a missing number(s) from an array.

What is the difficulty level of this exercise?

Test your Programming skills with w3resource's quiz.



PHP: Tips of the Day

How to Sort Multi-dimensional Array by Value?

Try a usort, If you are still on PHP 5.2 or earlier, you'll have to define a sorting function first:

Example:

function sortByOrder($a, $b) {
    return $a['order'] - $b['order'];
}

usort($myArray, 'sortByOrder');

Starting in PHP 5.3, you can use an anonymous function:

usort($myArray, function($a, $b) {
    return $a['order'] - $b['order'];
});

And finally with PHP 7 you can use the spaceship operator:

usort($myArray, function($a, $b) {
    return $a['order'] <=> $b['order'];
});

To extend this to multi-dimensional sorting, reference the second/third sorting elements if the first is zero - best explained below. You can also use this for sorting on sub-elements.

usort($myArray, function($a, $b) {
    $retval = $a['order'] <=> $b['order'];
    if ($retval == 0) {
        $retval = $a['suborder'] <=> $b['suborder'];
        if ($retval == 0) {
            $retval = $a['details']['subsuborder'] <=> $b['details']['subsuborder'];
        }
    }
    return $retval;
});

If you need to retain key associations, use uasort() - see comparison of array sorting functions in the manual

Ref : https://bit.ly/3i77vCC