问劳斯莱斯怎么买？

EN

<!DOCTYPE html>
<html lang='sv-se'>  
<head>
<title>Page Scroll</title>
<meta charset='utf-8'>
<script>
    const cars = [ [ 'Ford' ],[ 'Rolls Royce' ],[ 'Bentley' ],[ 'Volvo' ],];
</script>
<script>var page = 0;let length = cars.length;</script>
</head>

<body style='text-align:center;'>
<h1 id='page'>0</h1>
<h2 id='car'>Car</h2>
<button type='button' onclick='prevPage()'> PREV </button>
Scroll with the arrows
<button type='button' onclick='newPage()'> NEXT </button>

<p>The length of the data file: <a id='len'>0</a></p>

<script>
function newPage() {
    if (page > length - 2) {
      page = 0;
    } else {
      page += 1;
    }
    document.getElementById('page').innerHTML = page;
};
function prevPage() {
    if (page < 1) {
    page = length - 1;
    } else {
      page -= 1;
    }
    document.getElementById('page').innerHTML = page;
};
</script>

<script>
document.getElementById('car').innerHTML = (cars[page][0]);
document.getElementById('len').innerHTML = length; 
</script>
</body></html>