PHP Searching and Sorting Algorithm: Cocktail sort

PHP Searching and Sorting Algorithm: Exercise-7 with Solution

Write a PHP program to sort a list of elements using Cocktail sort.

Cocktail shaker sort (also known as bidirectional bubble sort, cocktail sort, shaker sort, ripple sort, shuffle sort, or shuttle sort ) is a variation of bubble sort that is both a stable sorting algorithm and a comparison sort. The algorithm differs from a bubble sort in that it sorts in both directions on each pass through the list. This sorting algorithm is only marginally more difficult to implement than a bubble sort and solves the problem of turtles in bubble sorts. It provides only marginal performance improvements, and does not improve asymptotic performance; like the bubble sort, it is not of practical interest, though it finds some use in education.

Visualization of shaker sort :

Sample Solution :

PHP Code :

<?php
function cocktailSort($my_array)
 {
	if (is_string($my_array))
	$my_array = str_split(preg_replace('/\s+/','',$my_array));
 
	do{
		$swapped = false;
		for($i=0;$i<count($my_array);$i++){
			if(isset($my_array[$i+1])){
				if($my_array[$i] > $my_array[$i+1]){
					list($my_array[$i], $my_array[$i+1]) = array($my_array[$i+1], $my_array[$i]);
					$swapped = true;
				}
			}			
		}
 
		if ($swapped == false) break;
 
		$swapped = false;
		for($i=count($my_array)-1;$i>=0;$i--){
			if(isset($my_array[$i-1])){
				if($my_array[$i] < $my_array[$i-1]) {
					list($my_array[$i],$my_array[$i-1]) = array($my_array[$i-1],$my_array[$i]);
					$swapped = true;
				}
			}
		}
	}while($swapped);
 
	return $my_array;
}
$test_array = array(3, 0, 2, 5, -1, 4, 1);
echo "Original Array :\n";
echo implode(', ',$test_array );
echo "\nSorted Array\n:";
echo implode(', ',cocktailSort($test_array)). PHP_EOL;
?>

Sample Output:

3, 0, 2, 5, -1, 4, 1                                                
Sorted Array :                                                      
-1, 0, 1, 2, 3, 4, 5

Flowchart :

PHP Code Editor:

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

Previous: Write a PHP program to sort a list of elements using Bubble sort.
Next: Write a PHP program to sort a list of elements using Comb sort.