title: cyclic negative number generation in C++
body: <p>I have requirement as follows.</p>
  
  <p>I have to generate increment negative numbers from -1 to -100 which is used a unique id for a request. Like it should be like this: -1, -2, -3, ...-100, -1, -2, and so on. How can I do this effectively? I am not supposed to use Boost. C++ STL is fine. I prefer to write simple function like int GetNextID() and it should generate ID. Request sample program on how to do this effectively?</p>
  
  <p>Thanks for your time and help</p>