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<?php $products = [1, 2, 3, 4, 5]; $vendors = ["Amazon", "Newegg", "Frys"]; $combinations = array(); function pc_permute($items, $perms = array()) { global $combinations; if (empty($items)) { //echo join(' ', $perms); //var_dump($perms); $combinations[] = $perms; } else { for ($i = count($items) - 1; $i >= 0; --$i) { $newitems = $items; $newperms = $perms; list($foo) = array_splice($newitems, $i, 1); array_unshift($newperms, $foo); pc_permute($newitems, $newperms); } } } pc_permute($products); var_dump($combinations);

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