Online PHP editor | refs for seLQX

<?php $array = [ ['Adams', 'King Street 12', '14:25', 'Heart Attack'], ['Ellis', 'Vine Street 4', '02:48', 'Broken Leg'], ['Adams', 'Parker Street 43', '20:10', 'Heart Attack'], ['Neil', 'Jack Street 9', '12:25', 'Broken Heart'], ['Colin', 'Queen Street 18', '05:48', 'Restless Leg'], ['Artemis', 'First Street 1', '10:17', 'Broken Leg'], ['Rufus', 'Long Street 5', '11:11', 'Dog Attack'], ]; $result = []; foreach ($array as $row) { if (isset($result[$row[3]])) { $result[$row[3]][] = $row; } elseif (isset($first[$row[3]])) { $result[$row[3]] = [$first[$row[3]], $row]; } else { $first[$row[3]] = $row; } } var_export($result);