Get all subsets of array

3 Months ago(Updated in 3 Months ago) PHP(Functions) 0

If you have a list of items (for example):

$arr = array(
 1 => null,
 2 => 1,
 3 => 2,
 4 => 3,
 5 => 3);

And you need all subsets of item index 1

1 -> 2, 3, 4, 5
2 -> 3, 4, 5
3 -> 4, 5
4 -> 
5 ->

 Our desired function:

function allSubsets($arr) {
    $result = array();
 
    foreach ($arr as $key => $value) {
        if ($value) {
            $result[$value][] = $key;
            $tmpResult = $result;
            foreach ($tmpResult as $index => $list) {
                if ($index >= $key) {
                    break;
                }
 
                foreach ($list as $i => $j) {
                    if ($value == $j) {
                        $result[$index][] = $key;
                    }
                }
            }
        }
    }
 
    return $result;
}

Example: 

$arr = array(
    1 => null,
    2 => 1,
    3 => 2,
    4 => 3,
    5 => 3);
 
print_r(allSubsets($arr));

Result:

Array
(
    [1] => Array
        (
            [0] => 2
            [1] => 3
            [2] => 4
            [3] => 5
        )

    [2] => Array
        (
            [0] => 3
            [1] => 4
            [2] => 5
        )

    [3] => Array
        (
            [0] => 4
            [1] => 5
        )
)

Recommended pages

File size calculator...

File size calculator function return file size format into kb, mb or gb. function file_size($size, $out = 'kb', $precision = 2) { switch ($out) { case 'kb': return round($...

URL Checker...

This function check if an url is valid or not. function is_valid_url($url) { return preg_match('|^http(s)?://[a-z0-9-]+(.[a-z0-9-]+)*(:[0-9]+)?(/.*)?$|i', $url); }...

Extract numbers from a unicode string...

Quick extract numbers from a unicode string......

PHP subwords() Function...

Function subwords, gets words by max num....

Comments

No comment here.
captcha image reload