ลบกวน ขอ code สุ่มตัวเลขที่ ที่ต้องให้ สุ่ม หน่อยครับผม

function random_num(){
   for($i=1;$i<=4;$i++){
      $arr[] = rand(0,9999);
   }
   return $arr;
}

$arr_num1 = random_num();

$a=array(77,81,50,60,32,41,25,356,7897,465);

function newRand($ar){

     $b=$ar;
     $c=array();

     for($i=0; $i<4; $i++){

          $j=rand(0, count($b)-1);
          $c[]=$b[$j]; $b[$j]=null;

     }
     return $c;

}


print_r(newRand($a));
print_r(newRand($a));

<?php
$str = array("77","81","50","60","32","41","25","356","7897","465");
$random_keys=array_rand($str,4);
echo $str[$random_keys[0]]."<br>";
echo $str[$random_keys[1]]."<br>";
echo $str[$random_keys[2]]."<br>";
echo $str[$random_keys[3]];
?>