How do you get rid of gnats and other small bugs?

i made the mistake of leaving my window open today and now atleast a dozen small gnats and several beetle like bugs are now swarming over my light in my room. whats the best way to kill them? should i just let them live their short lives and die?(i will be away for several days starting tomorrow so they won't bother me) or should i hunt them with "off" and make an effort to kill them all myself? i will be spring cleaning soon so the remains will be cleaned either way. thank you.