stl const_iterator question.

[Fenglou Mao]

Hi, all,
    I want to use an interator of this type:

       set<MyObject, lt<MyObject> >::iterator  i;

    I think I can use statement like this:

    1.      (*i).x+=1.0;

     or

    2.      MyObject& t=*i;

    But the g++ compiler always think "i" is a const_iterator,
it give error for 1, and warning for 2.

    Who can tell me why?

Sincerely Yours,

FengLou Mao
*******************************
ADD:Mr. FengLou Mao
    Institute of Physical Chemistry
    Peking University
    BeiJing
    P.R.China
Tel:86-10-62756833
Fax:86-10-62751725