What is the shortest way of checking if JS value exists?
<p>Assuming I have this :</p>

<pre><code>var a = parseInt(prompt("Enter A"));
var b = parseInt(prompt("Enter B"));
var c = parseInt(prompt("Enter C"));
</code></pre>

<p>What  is the <em>shortest</em> way to check if a value exists in all 3 variables ?</p>

<p>Doing    <code>if(a  &amp;&amp; b &amp;&amp; c)</code>  is <em>not</em> accurate cause <code>0</code> is falsy.</p>

<p><em>p.s. <strong>a,b,c can be ints or strings</strong>...Also , There must be a trick here...</em></p>

<p>for the string example  : </p>

<pre><code>var a = (prompt("Enter A"));
var b = (prompt("Enter B"));
var c = (prompt("Enter C"));
</code></pre>
