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<?php $array = [ ["444", "0081"], ["449", "0081"], ["451", "0081"], ["455", "2100"], ["469", "2100"] ]; $result = []; foreach ($array as $row) { if (!isset($ref[$row[1]])) { $ref[$row[1]] = $row; $result[] = &$ref[$row[1]]; } else { $ref[$row[1]][0] .= ',' . $row[0]; } } var_export($result);
Output for 8.0.1 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
array ( 0 => array ( 0 => '444,449,451', 1 => '0081', ), 1 => array ( 0 => '455,469', 1 => '2100', ), )
preferences:
115.29 ms | 402 KiB | 91 Q