Sub array merge in 2D array according to key using PHP

php_subarray_merge_in_2D_array_according_to_key.php

<?php
    $source = array( 
                        array("1" => 5), 
                        array("2" => 1525),
                        array("2" => 12365), 
                        array("2" => 34234), 
                        array("3" => 324234)
                    );
    
    $result = array();
    foreach($source as $item) {
        $artist = key($item);
        $album = current($item);
        if(!isset($result[$artist])) {
            $result[$artist] = array();
        }
        $result[$artist][] = $album;
    }
    echo "<pre>";
    print_r($result);

/*
Result:
Array
(
    [1] => Array
        (
            [0] => 5
        )

    [2] => Array
        (
            [0] => 1525
            [1] => 12365
            [2] => 34234
        )

    [3] => Array
        (
            [0] => 324234
        )

)
*/    
?>