Runtime error

Hello everybody,

I think i am having a problem with my compiler(or with my logic) since yesterday whenever I use a loop (for, while, do...while) the program gives the error:

This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.

I am using Dev-C++ version 4.9.8.3 on Windows Vista Ultimate.

I include the source code of my latest confussion:

Code:

string ExpandString(string Sentence)
{
   
   int centerpos;
   
       for(int i=Sentence.size();Sentence.size()<40;i++)
       { 
              string tinystring=Sentence.substr(centerpos,1);
              Sentence.insert(centerpos,tinystring);
              centerpos--;
              tinystring=Sentence.substr(centerpos,1);
              Sentence.insert(centerpos,tinystring);
       }
       
       return Sentence;     
}

just a wild guess -
centerpos is used uninitialized (you didn't give it a value before using it)

Brilliant Cyberfish!!! Seems I have been high on something for the last two days... all my loops were nuts.. Thnks again