title: PHP - check if number is prime
body: <p>I'm trying to create a function which checks whether the number is prime or not. BUT I want this function to echo to the user 'prime' or 'NOT prime' - and that's where my problem starts. 
  Let me show you my code:</p>
  
  <pre><code>class IsPrime
  {       
      function check($num)
      {
          for ($i = 2; $i &lt; $num; $i++)
          {
              if ($num % $i == 0) 
              {
                  echo 'NOT prime';
                  break;
              }               
          }
          echo 'Prime';           
      }       
  }
  
  $x = new IsPrime();
  $x-&gt;check(4);
  </code></pre>
  
  <p>The problem is that when I put any prime number - it works correctly, but when I put any not prime number - it also echos second echo, sth like this: <code>'NOT prime prime'</code>.</p>
  
  <p>How can I make it echo only the right answer ?</p>