Exam score estimations.. nearly impossible

I just had my first examination in my Master’s in Computer Science and Engineering. After three hours of mental torture, I decided that was the best I could do and delivered the work. Next, I looked at the points I could achieve for each question to estimate my total score… And frankly, I have no idea. Each question was worth a number of points, worth 90 in total. Add 10 and divide by 10 to determine your score. But I have no idea how the points are given. If I make mistakes, how much is subtracted? If I didn’t apply the techniques, but did reason about the result, is that worth anything? Looking at it from a reasonable point of view, I think I passed the examination, but it’s frustrating that I can’t know for sure with this subject, because the questions entailed a lot of work. The only subjects of which I’ve succesfully been able to estimate my score were subjects in Mathematics or Logic. If only it were that simple again…