phrase split algorithm in PHP
<p>Not sure how to explain. Let's use an example. Say I want to split the sentence</p>

<p>"Today is a great day."</p>

<p>into</p>

<pre><code>today
today is
today is a
today is a great
today is a great day
is
is a
is a great
is a great day
a
a great
a great day
great
great day
day
</code></pre>

<p>The idea is to get all the sequential combination in a sentence.</p>

<p>I have been thinking what's the best way to do it in PHP. Any idea is welcome. </p>
