    // @(#)root/vmc:$Name:  $:$Id: TVirtualMCApplication.cxx,v 1.3 2004/02/10 13:46:37 brun Exp $
    // Author: Ivana Hrivnacova, 27/03/2002

    #include "TVirtualMCApplication.h"
    #include "TError.h"

    //______________________________________________________________________________
    //
    // Interface to a user Monte Carlo application.
    //______________________________________________________________________________

    ClassImp(TVirtualMCApplication)

    TVirtualMCApplication* TVirtualMCApplication::fgInstance = 0;

    //_____________________________________________________________________________
    TVirtualMCApplication::TVirtualMCApplication(const char *name,
                                                 const char *title)
      : TNamed(name,title)
    {
    //
    // Standard constructor
    //

      if (fgInstance) {
        Fatal("TVirtualMCApplication",
              "Attempt to create two instances of singleton.");
      }

      fgInstance = this;
    }

    //_____________________________________________________________________________
    TVirtualMCApplication::TVirtualMCApplication()
      : TNamed()
    {
      //
      // Default constructor
      //
      fgInstance = this;
    }

    //_____________________________________________________________________________
     TVirtualMCApplication::~TVirtualMCApplication()
    {
      //
      // Destructor
      //

      fgInstance = 0;
    }