title: c++ member function access private static variable?
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/7092765/what-does-it-mean-to-have-an-undefined-reference-to-a-static-member">What does it mean to have an undefined reference to a static member?</a>  </p>
  </blockquote>
  
  
  
  <p>I don't know why I got error "undefined reference to `TT::i'" if I implement the function outside of class declaration?
  Here is the code..</p>
  
  <pre><code>class TT{
  private:
      static int i;
  public:
      void t();
  };
  
  void TT::t(){
      i=0;
  }
  </code></pre>