Click on HTML table and get row number (with Javascript, not jQuery)

function  getId(element) {
    alert("row" + element.parentNode.parentNode.rowIndex + 
    " - column" + element.parentNode.cellIndex);
}

<table>
  <tr>
    <td><input type="button" value="button" onclick="getId(this)"></td>
    <td><input type="button" value="button" onclick="getId(this)"></td>
    <td><input type="button" value="button" onclick="getId(this)"></td>
  </tr>
  <tr>
    <td><input type="button" value="button" onclick="getId(this)"></td>
    <td><input type="button" value="button" onclick="getId(this)"></td>
    <td><input type="button" value="button" onclick="getId(this)"></td>
  </tr>
  <tr>
    <td><input type="button" value="button" onclick="getId(this)"></td>
    <td><input type="button" value="button" onclick="getId(this)"></td>
    <td><input type="button" value="button" onclick="getId(this)"></td>
  </tr>
</table>