You are trapped in a room with two doors. One leads to certain death and the other leads to freedom. You don't know which is whi
ch. There are two robots guarding the doors. They will let you choose one door but upon doing so you must go through it.
You can, however, ask one robot one question. The problem is one robot always tells the truth ,the other always lies and you don't know which is which.
Which door has danger behind it? the robot that lies will tell us which and then we will know that is the door we have to go through because the robot had lied
