Huge thief ant problem?

-So then, i've had ants for a while, but i really never bothered with them because there were only 1-2 crawling around. Recently they are almost everywhere in my home, and i can't get rid of them. I've tried to trace them, and i saw hundreds of them in my room. They are traveling through the balcony in my room, and they are closely sticking to the walls, and going across my room. I can't keep tracing them because my bed/Computer table is in front of me. I'm not sure how should i deal with this, killing them one by one isn't going to help, that's for sure. Any tips what should i do? I don't get it how could they get to the 4th floor -.-!i heard hairspray works fine for spiders but im not sure if that works for ant :S

and theres some ant poison but im not sure where u get it :S
I've heard that human semen is an effective and safe ant poison.