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<?php function sum() { $list = array(); $prepare = function($value) use(&$prepare, &$list) { if (is_array($value)) { return $prepare(array_merge($list, $value));//array_map($prepare, ); } $list[] = $value; }; $args = func_get_args(); array_walk($args, $prepare, $list); var_dump($list); return addition(0, $list); } function addition($sum, array &$list) { return empty($list) ? $sum : addition($sum + array_pop($list), $list); } $vars = range(1, 10); echo sum(array($vars), array(1));

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