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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, $num); //Loop through each possible combination for ($i = 0; $i < $total; $i++) { $ff=''; //For each combination check if each bit is set for ($j = 0; $j < $num; $j++) { //Is bit $j set in $i? if (pow(2, $j) & $i) $ff = $ff.''.$array2[$j]; } $temp[]=$ff; } print_r(array_shift($temp));

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