<?php
$chars = array("a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p",
"q","r","s","t","u","v","w","x","y","z","0","1","2","3","4","5","6","7","8","9");

$adet=$_GET['adet'];

$uzunluk=strlen($adet);
$current="";
for($i=0;$i<$uzunluk;$i++){
$current.=$chars[rand(0,25)];  
}
echo $current;

?>