Checkerboard with row and columns

I looked for the answeer and i find nothing about it. So my question is how can i make a checkerboard with just using js. When i open the site, it should askes the user how many rows and columns they want to have so if i say 5 rows and 5 columns it should generate a checkerboard with this. I should use a for-loop and if for this. Heres my Code i worked on.

  <script type="text/javascript">

      var row = prompt("Rows?", 10);
      row = parseInt(row);
      var column = prompt("Columns?", 10);
      column = parseInt(column);

      for(var i= 1;i<=column;i++)
      {
        for(var p= 1;p<=row;p++)
        {
          if(p % 2 == 0)
          {
            document.write(' <img src="schwarz.png" ' + "<br />");

        {

          document.write(' <img src="weiss.png" ' + "<br />");
        }
      }
    }
  }
  </script>