find selected checkboxes with jQuery
<p>I have this structure:  </p>

<pre class="lang-html prettyprint-override"><code>&lt;div id="fields" class="grid"&gt;
    &lt;div&gt;...&lt;div&gt;
    &lt;div id="some_id_1" class="itemSortable"&gt;
        &lt;input ...&gt;
        &lt;input ...&gt;
        &lt;div&gt;
            &lt;input id="selected" name="selected" type="checkbox" value="true"&gt;
            &lt;input name="selected" type="hidden" value="false"&gt;
            ...
        &lt;/div&gt;
    &lt;div id="some_id_2" class="itemSortable"&gt;
        &lt;input ...&gt;
        &lt;input ...&gt;
        &lt;div&gt;
            &lt;input id="selected" name="selected" type="checkbox" value="true"&gt;
            &lt;input name="selected" type="hidden" value="false"&gt;
            ...
        &lt;/div&gt;
     ...
    &lt;div id="some_id_n" class="itemSortable"&gt;
        &lt;input ...&gt;
        &lt;input ...&gt;
        &lt;div&gt;
            &lt;input id="selected" name="selected" type="checkbox" value="true"&gt;
            &lt;input name="selected" type="hidden" value="false"&gt;
            ...
        &lt;/div&gt;
&lt;/div&gt;
</code></pre>

<p>I have no experience with jQuery so I am stuck. Can somebody help with jQuery script to get an array of all ids (Eg. <code>some_id_x</code>) for selected checkboxes?</p>
