array line

<?php
$list=array(1,2,3,4,5,6);

$line=0;
foreach($list as $value){
$line+=1;

if($line>4){
$line=1;
}
echo "$value :$line<br>";


}

?>

1 :1
2 :2
3 :3
4 :4
5 :1
6 :2