PHP Ds\Set sort() Function

The Ds\Set::sort() function of DS\Set class in PHP is used to in-place sort the elements of a specified Set instance according to the values. By default, the Set is sorted according to the increasing order of the values.

Syntax:

void public Ds\Set::sort ([ callable $comparator ] )

Parameters: This function accepts a comparator function according to which the values will be compared while sorting the Set. The comparator should return the following values based on the comparison of two values passed to it as a parameter:

• 1: if the first element is expected to be less than second element.
• -1: if the first element is expected to be greater than second element.
• 0: if the first element is expected to be equal to the second element.

Return value: The function does not returns any value. It just sorts the specified Set instance according to the comparator function passed.

Below programs illustrate the Ds\Set::sort() function:

Program 1:

<?php
// PHP program to illustrate Ds\Set::sort() function

$set = new \Ds\Set([20, 10, 30]);

// sort the Set
$set->sort();

// Print the sorted Set
print_r($set);

?>

Output:

Ds\Set Object
(
    [0] => 10
    [1] => 20
    [2] => 30
)

Program 2:

<?php
// PHP program to illustrate sort() function

$set = new \Ds\Set([20, 10, 30]);

// Declaring comparator function
$comp = function($first, $second){
        if($first>$second)
            return -1;
        else if($first<$second)
            return 1;
        else
            return 0;
};

// sort the Set using comparator
$set->sort($comp);

// Print the sorted Set
print_r($set);

?>

Output:

Ds\Set Object
(
    [0] => 30
    [1] => 20
    [2] => 10
)

Reference: http://php.net/manual/en/ds-set.sort.php