Click on RENDER to render in all of the clones. Wait until the room is filled with the clones. Click START button to begin simulation. Drag away any troublemakers that are clogging the lines. (The clones are draggable.)
What happens if 300 people are put into a rectangular room, and then they all want to get out through a single exit? Somebody yelled FIRE in a movie theater! Coding and design by me. Maybe I'll do another one with a sports stadium...