title: Only ahow error message when error occurs
body: <p>I am creating a calculator on the web to challenge my ability to think an challenge my creative edge and i got the basics down it works but the issue i am having is the error displaying whem there is no error is just displays when the page loads and then displays the value when the calculator is used can someone please help?</p>
  
  <pre><code>&lt;?php
  
  $value1 = $_POST['value1'];
  $symbol = $_POST['operator'];
  $value2 = $_POST['value2'];
  $nulr = "nulrl";
  
  if($nulr === "nulrl"){
  if($symbol === "+"){
  $output = $value1 + $value2;
  } elseif($symbol === "-"){
  $output = $value1 - $value2;
  } elseif($symbol === "/"){
  $output = $value1 / $value2;
  } elseif($symbol === "*"){
  $output = $value1 * $value2;
  } else{
  $output = "Error could not perform operation";
  }
  
  }
  echo $output;
  ?&gt;
  </code></pre>
  
  <p>EDIT 
  Here is my html code</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html lang="en"&gt;
  &lt;head&gt;
  &lt;title&gt;The Calculator&lt;/title&gt;
  &lt;meta charset="utf-8"&gt;
  &lt;link rel="stylesheet" href="styles.css"&gt;
  &lt;/head&gt;
  &lt;body&gt;
  &lt;header&gt;
  &lt;h1&gt;The Goal&lt;/h1&gt;
  &lt;p&gt;Through my studies of coding languages i have come to realize that  just about every coding langauage no matter how different the syntax can  handle user input and variables and produce and output. With this being said i wanna make an interactive calculator for each coding language and then advance on each one and see which language can produce the best  calculator!&lt;/p&gt;
  
  &lt;main&gt;
  &lt;h2&gt;PHP Calculator&lt;/h2&gt;
  &lt;form method="post"&gt;
  &lt;input type="number" name="value1" value="value1" class="number-box"&gt;
  &lt;br&gt;
  &lt;select name="operator"&gt;
  &lt;option value="+"&gt;+&lt;/option&gt;
  &lt;option value="-"&gt;-&lt;/option&gt;    
  &lt;option value="*"&gt;*&lt;/option&gt;
  &lt;option value="/"&gt;/&lt;/option&gt;
  &lt;/select&gt;
  &lt;br&gt;
  &lt;input type ="number" name="value2" value="value2" class="number-box"&gt;
  &lt;br&gt;
  &lt;input type ="submit" name="submit" class="submit-button"&gt;
  &lt;/form&gt;
  &lt;?include("calculator.php")?&gt;
  
  &lt;footer&gt;
  &lt;h3&gt;Comment Box&lt;/h3&gt;
  &lt;form method="post" action="comment.php"&gt;
  &lt;input type="text" value="name" name="name"&gt;
  &lt;br&gt;
  &lt;textarea name="comment"&gt;Comments&lt;/textarea&gt;
  &lt;input type="submit" name="submit" class="submit-button"&gt;
  &lt;/form&gt;
  
  &lt;?php
  echo file_get_contents("comments.txt");
  ?&gt;
  &lt;/footer&gt;
  
  
  &lt;/main&gt;
  &lt;/header&gt;
  </code></pre>
  
  <p>
     </p>
  
  <p>EDIT:
  Still have not recieved any correct answers</p>