Converting form lowercase to uppercase?
<p>How can I convert a string from a lowercase to uppercase with all possible outputs?</p>

<p>For example, I have the string <code>'abc'</code>; it must give all possible outputs in uppercase to show this set of strings as output:</p>

<pre><code>'abC','aBc,'aBC','Abc'ABc','AbC','ABC' 
</code></pre>
