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PHP Array Exercises : Sort an array of positive integers using the Bead-Sort Algorithm

PHP Array: Exercise-10 with Solution

Write a PHP program to sort an array of positive integers using the Bead-Sort Algorithm.

According to Wikipedia "Bead-sort is a natural sorting algorithm, developed by Joshua J. Arulanandham, Cristian S. Calude and Michael J. Dinneen in 2002. Both digital and analog hardware implementations of bead sort can achieve a sorting time of O(n); however, the implementation of this algorithm tends to be significantly slower in software and can only be used to sort lists of positive integers".

Input array : Array ( [0] => 5 [1] => 3 [2] => 1 [3] => 3 [4] => 8 [5] => 7 [6] => 4 [7] => 1 [8] => 1 [9] => 3 )

Sample Solution:

<?php
function columns($uarr)
{
$n=$uarr;
if (count($n) == 0)
 return array();
else if (count($n) == 1)
 return array_chunk($n[0], 1);
array_unshift($uarr, NULL);
 $transpose = call_user_func_array('array_map', $uarr);
return array_map('array_filter', $transpose);
}
function bead_sort($uarr)
{
foreach ($uarr as $e)
 $poles []= array_fill(0, $e, 1);
return array_map('count', columns(columns($poles)));
}
echo 'Original Array : '.'
';
print_r(array(5,3,1,3,8,7,4,1,1,3));
echo '
'.'After Bead sort : '.'
';
print_r(bead_sort(array(5,3,1,3,8,7,4,1,1,3)));
?>

Sample Output:

Original Array :                                            
Array                                                       
(                                                           
    [0] => 5                                                
    [1] => 3                                                
    [2] => 1                                                
    [3] => 3                                                
    [4] => 8                                                
    [5] => 7                                                
    [6] => 4                                                
    [7] => 1                                                
    [8] => 1                                                
    [9] => 3                                                
)                                                           
                                                            
After Bead sort :                                           
Array                                                       
(                                                            
    [0] => 8                                                
    [1] => 7                                                
    [2] => 5                                                
    [3] => 4                                                
    [4] => 3                                                
    [5] => 3                                                
    [6] => 3                                                
    [7] => 1                                                
    [8] => 1                                                
    [9] => 1                                                
) 

Flowchart:

Flowchart: Sort an array of positive integers using the Bead-Sort Algorithm

PHP Code Editor:

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PHP: Tips of the Day

Convert a PHP object to an associative array

Just typecast it

$array = (array) $yourObject;

From Arrays:

If an object is converted to an array, the result is an array whose elements are the object's properties. The keys are the member variable names, with a few notable exceptions: integer properties are unaccessible; private variables have the class name prepended to the variable name; protected variables have a '*' prepended to the variable name.These prepended values have null bytes on either side.

Example: Simple Object

$object = new StdClass;
$object->foo = 1;
$object->bar = 2;

var_dump( (array) $object );

Output:

array(2) {
  'foo' => int(1)
  'bar' => int(2)
}

Example: Complex Object

class Foo
{
    private $foo;
    protected $bar;
    public $baz;

    public function __construct()
    {
        $this->foo = 1;
        $this->bar = 2;
        $this->baz = new StdClass;
    }
}

var_dump( (array) new Foo );

Output (with \0s edited in for clarity):

array(3) {
  '\0Foo\0foo' => int(1)
  '\0*\0bar' => int(2)
  'baz' => class stdClass#2 (0) {}
}

Output with var_export instead of var_dump:

array (
  '' . "\0" . 'Foo' . "\0" . 'foo' => 1,
  '' . "\0" . '*' . "\0" . 'bar' => 2,
  'baz' =>
  stdClass::__set_state(array(
  )),
)

Typecasting this way will not do deep casting of the object graph and you need to apply the null bytes (as explained in the manual quote) to access any non-public attributes. So this works best when casting StdClass objects or objects with only public properties. For quick and dirty (what you asked for) it's fine.

Also see this in-depth blog post:

  • Fast PHP Object to Array conversion

Ref : https://bit.ly/3fqiV2E