    <!DOCTYPE html>
    <html>
    <head>
      <meta charset="UTF-8">
      <title>배열 만들고 출력하기</title>
      <link rel="stylesheet" href="style_js.css">
    <body>
      <script>
        let arr = new Array();    // arr = []와 같음
        let sum = 0;
        arr[0] = 23;
        arr[1] = 12;
        arr[2] = 34;
        for (let i = 0; i < arr.length; i++){
          document.write(`arr[${i}] = ${arr[i]}<hr>`);
          sum = sum + arr[i];
        }
        document.write(`배열을 더한 값은 ${sum}`);
      </script>
    </body>
    </html>