title: How to resolve "'UnityEngine.Random' does not contain a definition for 'Next' ..." error?
body: <p>i am writing a game in unity and i want to create
  one random integer number... i am using the following:</p>
  
  <pre><code>public Random ran = new Random();
  public int power = ran.Next(0, 10);
  </code></pre>
  
  <p>but when i want to run the program it gives me the following error:</p>
  
  <blockquote>
    <p>Type 'UnityEngine.Random' does not contain a definition for 'Next' and no
    extension method 'Next' of type `UnityEngine.Random' could be found 
    (are you missing a using directive or an assembly reference?)</p>
  </blockquote>
  
  <p>Does anyone help me on what is going wrong ???</p>