You still have the same issue — you're advancing the iterator after erasing the corresponding element from the set. The reason it works on your PC is that it's undefined behavior, and would most likely cause a runtime error on your PC as well with bigger inputs. It seems you didn't perhaps understand my code, so here's a link with a few alternative solutions to the issue as one of them might be easier to understand: http://stackoverflow.com/questions/2874441/deleting-elements-from-stl-set-while-iterating.