function judge($a,$x){
$ca = count($a);
$xa = [];
for($i = 0,$j = $ca -1;$i<$j;)
{
$s = $a[$i] + $a[$j];
if($s == $x) {
$xa[] = [$a[$i],$a[$j]];
}elseif($s < $x){
$i++;
}elseif ($s > $x){
$j--;
}
}
return $xa;
}