everybody. I wanna make a for loop outputting my h3 elements.  I could do it for one of them but to have them all, it doesn't output the content.
And the a in the loop is for making inner links of my h3 in a long page.
function showH() {
  var x = document.getElementsByTagName("H3");
  let str = '<a href="">';
  for (var i =0; i < x.length; i++) {
    str += x[i] + "</a>";
  }
  document.getElementById("get").innerHTML = str;
}
<p id="get"></p>
<button onclick="showH()">click</button>
this code outputs:
[object HTMLHeadingElement][object HTMLHeadingElement][object HTMLHeadingElement][object HTMLHeadingElement]