For the 20 destructible bulbs and 100 floors, what's the fewest number of tries? I thought of this way: start at floor 50 and drop bulb 1. If it breaks, go to floor 25, if not, go to floor 75. Keep going to the floor halfway between the last floor and the boundary you want to test. You can do it in about 8 tries. Is there a way to do it in fewer tries?
