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<?php function make_recursive($arr, $root = 0, $pid = 'pid', $id = 'id', $child = 'child') { $m = array(); foreach ($arr as $e) { if (!isset($m[$e[$pid]])) $m[$e[$pid]] = array(); if (!isset($m[$e[$id]])) $m[$e[$id]] = array(); $m[$e[$pid]][] = array_merge($e, array($child => &$m[$e[$id]])); } return $m[$root][0]; } $arr = array( array('id' => 5273, 'pid' => 0, 'name' => 'John Doe'), array('id' => 6032, 'pid' => 5273, 'name' => 'Sally Smith'), array('id' => 6034, 'pid' => 6032, 'name' => 'Mike Jones'), array('id' => 6035, 'pid' => 6034, 'name' => 'Jason Williams'), array('id' => 6036, 'pid' => 5273, 'name' => 'Sara Johnson'), array('id' => 6037, 'pid' => 5273, 'name' => 'Dave Wilson'), array('id' => 6038, 'pid' => 6037, 'name' => 'Amy Martin'), ); $re=make_recursive($arr); var_export($re);

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