How to find matching words?
<p>Write a program (in php) to look up the dictionary word for crossword puzzles. On the website the user types in the word form, replacing each letter with an underscore missing lower ('_'). As a result he gets a list of words that match a given pattern.</p>

<pre><code>*Dictionary file (dictionary_file.txt)
dog 
dos
tag
sleep
door
clouds*
</code></pre>

<p>For example: do_</p>

<pre><code>Output: 
dog
dos
</code></pre>
