Arranging corresponding values in descending manner
<p>I have two sets of columns right now but I am not sure how do I program it and what set of class for me to use it. Both are in separate arrays. One for letters and the other for the numbers.</p>

<pre><code> a  12
 b  9
 c  156
</code></pre>

<p>So a corresponds to 12 and b corresponds to 9 etc etc. The list is actually a frequency of letters in a text file so I have 26 of them.
Both are not in the same array. As I have separate arrays for both of them. I want to try and arrange
and make them be in a descending manner.
So that the output would be:</p>

<pre><code> c   156
 a   12
 b   9    
</code></pre>

<p>I'm still unsure about various capabilities of ArrayList or HashMap or Tree Map. So any help with this?</p>
