$a=array(1,2,3);
 for($i=0;$i<sizeof($a);$i++)
 {
     echo $a[$i];
 }
 unset($a[0]);
 
 for($i=0;$i<sizeof($a);$i++)
 {
     echo $a[$i];
 } 

 $a=array(1,2,3);
 for($i=0;$i<sizeof($a);$i++)
 {
     echo $a[$i];
 }
 unset($a[0]);
 
 
 while(list($k,$v)=each($a))
 {
     echo $k.'->'.$v."<br/>";
 }
  

<?php
$a = array(1 => 'one', 2 => 'two', 3 => 'three');
unset($a[2]);
/* will produce an array that would have been defined as
   $a = array(1 => 'one', 3 => 'three');
   and NOT
   $a = array(1 => 'one', 2 =>'three');
*/

$b = array_values($a);
// Now $b is array(0 => 'one', 1 =>'three')
?>