3v4l.org

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<?php $array1 = array('A', 'B'); $array2 = array('1', '2', '3'); $num = count($array2); //The total number of possible combinations $total = pow(2, $num); $temp = array(); //Loop through each possible combination for ($i = 0; $i < $total; $i++) { //For each combination check if each bit is set for ($j = 0; $j < $num; $j++) { //Is bit $j set in $i? if (pow(2, $j) & $i) $temp[] = $words[$j]; } } print_r($temp);

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