Sum of natural number in PHP

/*
 * sum of natural number
 * */
$x = 8;
$result = $x;
while($x--){
  $result += $x;
}
echo $result;
/*
 * sum of natural number in another way
 * */
$x = 8;
$result = 0;
while($x){
  $result += $x--;
}
echo $result;