C++ Expression

I have one last task in my compiler class, which is counting simple C++ expression, using unary operator, such as a+b--+c or something like that. It was a simple task, but it's hard to do. I try to finish this task using PHP, since it was the most common programming language for me. I rarely use visual programming, such as Delphi or Visual Basic, since it requires a lot of object and my lecturer is using GNU/Linux for his operating system, and that would take him a hard way to check my task. He have to find another computer that uses Microsoft Windows.

The task's deadline is long enough, just before our final test, which will be held on December 4th. I have left this task unupdated for a long time, since i'm working on another big task. Now that i have finished my other task, i will continue finishing my compiler task. Today i tried to do some updates and i managed to get a big loop in this progress. The lecturer has given an instruction or algorithm to do the calculation process, and there were four steps. I have done 3 of them. I just need the final steps and this is the hardest thing, since i have to save the original values before i made a change and restore the value when i'm finished calculating. Hopefully in this week i can finish this task and submit this to my lecturer.