title: PHP if(){} does not echoes vars got from html
body: <p>All I need is: 
  1. After pressing 'submit' button to get vars to function and use return value.
  2. To understand why I can not echo functions return value; </p>
  
  <p><strong>PHP FUNCTION:</strong></p>
  
  <pre><code>function check_if_numbers($x, $y)
  {   
          $permission =0;
          if((gettype($x)==gettype($y))&amp;&amp;(gettype($x)=="integer")) {return 1;}
          else {return 0;}
  }
  </code></pre>
  
  <p><strong>PHP CODE</strong></p>
  
  <pre><code>&lt;?php
      if( isset($_GET['submit']) )
      {
          $x = htmlentities($_GET['x']);
          $y = htmlentities($_GET['y']);
          $permission_token=check_if_numbers($x, $y);
          echo $permission_token;
      }
  ?&gt;
  </code></pre>
  
  <p><strong>HTML</strong></p>
  
  <pre><code>&lt;form action="" method="get"&gt;
  Determine X = &lt;input name='x' id='x' type="text" size="1"&gt;&lt;/br&gt;
  Determine Y = &lt;input name='y' id='y' type="text" size="1"&gt;&lt;/br&gt;
  &lt;font size=2 &gt;Input only integers&lt;/font&gt;
  &lt;input type="submit" value="submit"&gt;
  </code></pre>