3v4l.org

run code in 300+ PHP versions simultaneously
<?php $array = array ( 0 => array ( 'company' => 1, 'product' => 5, ), 1 => array ( 'company' => 2, 'product' => 4, ), 2 => array ( 'company' => 6, 'product' => 5, ), 3 => array ( 'company' => 2, 'product' => 3, ), ); foreach ($array as $set) { if (!isset($result[$set['product']])) { $result[$set['product']] = $set; } else { $result[$set['product']]['company'] .= ",{$set['company']}"; } } var_export(array_values($result));
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
array ( 0 => array ( 'company' => '1,6', 'product' => 5, ), 1 => array ( 'company' => 2, 'product' => 4, ), 2 => array ( 'company' => 2, 'product' => 3, ), )
preferences:
105.47 ms | 408 KiB | 5 Q