C++ correction

Hi /prog/

http://pastebin.com/meb2ac2d

Line 45, part of find_idea_id().

I want to give 'it' a default value, null pointer. It won't compile, can't understand how it should be typed differently.

Help me out :3

>>2
removing the '&' doesn't help, still the same error message. Hm, I'll post it, might be useful

./Idea Registry/idea_registry.h:45: error: default argument for parameter of type ‘__gnu_cxx::__normal_iterator<Idea_Registry::Idea*, std::vector<Idea_Registry::Idea, std::allocator<Idea_Registry::Idea> > >&’ has type ‘int’

flags: -std=c++98 -pedantic -Wall -Wextra