Well, you have to multiply it by the number of translation units. Also, I like the point made in the sibling comment by moefh. Are you sure you don't need to

Well, you have to multiply it by the number of translation units. Also, I like the point made in the sibling comment by moefh. Are you sure you don't need to tokenize? Can I see your implementation? I have looked at a few implementations of C preprocessors, and they're not simple.