3v4l.org

run code in 300+ PHP versions simultaneously
<?php $a1 = [1, 2, 3]; $a2 = [4, 7, 10]; $a3 = [5, 6, 8, 9]; $it1 = new ArrayIterator($a1); $it2 = new ArrayIterator($a2); $it3 = new ArrayIterator($a3); $m = new ArrayIterator([$it1, $it2, $it3]); foreach(new \RecursiveIteratorIterator($m) as $v) { var_dump($v); }

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44.17 ms | 402 KiB | 5 Q