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<?php function add() { $list = array(); $prepare = function($value) use(&$prepare, &$list) { if (is_array($value)) { return array_map($prepare, array_merge($list, $value)); } $list[] = $value; }; return false === array_walk(func_get_args(), $prepare, $list) ? 0 : addition(0, $list); } function addition($sum, array &$list) { return empty($list) ? $sum : addition($sum + array_pop($list), $list); }
Output for 5.4.2 - 5.4.45, 5.5.24 - 5.5.35, 5.6.7 - 5.6.28, 7.0.0 - 7.0.20, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
preferences:
178.33 ms | 404 KiB | 257 Q