Why does _=$=+[],++_+''+$ evaluate to 10
<p>I saw <code>_=$=+[],++_+''+$</code> that evaluates to <code>10</code> in this question <a href="http://stackoverflow.com/questions/7202157/can-you-explain-why-10">Can you explain why ++[[]][+[]]+[+[]] = 10</a>. ( <a href="http://jsfiddle.net/tVMqM/" rel="nofollow">http://jsfiddle.net/tVMqM/</a> ).</p>

<p>Can someone please explain me why?</p>
