JSFiddle - React, Tailwind, and code Playground
by matthias_h
HTML
<table>
<tr>
<td>
<img id="pos1" src="slicedImg_01.gif" onclick="change(1)" />
<img id="pos2" src="slicedImg_02.gif" onclick="change(2)" />
</td>
<tr>
<td>
<img id="pos3" src="slicedImg_03.gif" onclick="change(3)" />
<img id="pos4" src="slicedImg_04.gif" onclick="change(4)" />
</td>
</tr>
</tr>
</table>
JavaScript
var image_array = $("img").map(function () {
return $(this).attr("src");
});
images = jQuery.unique(image_array);
alert(images.length);