$words=array('A','B','C');
function rand_S($arr){
$num = count($arr);
$total = pow(2, $num);
$m=null;
for ($i = 0; $i < $total; $i++) {
for ($j = 0; $j < $num; $j++) {
if (pow(2, $j) & $i)$m.=$arr[$j];
}
if($m)$array[]=$m;
$m=null;
}
return $array;
}
var_dump(rand_S($words));
结果如下
Array ( [0] => A [1] => B [2] => AB [3] => C [4] => AC [5] => BC [6] => ABC )