Riddle: Robots on a Line
Two robots are placed at different points on a straight line of infinite length. When they are first placed down, they each spray out some oil to mark their starting points.
You must program each robot to ensure that the robots will eventually crash into each other. A program can consist of the following four instructions:
- Go left one space
- Go right one space
- Skip the next instruction if there is oil in my current spot
- Go to a label
A robot will carry out one instruction per second. Both robots need not have the same program. Note that you won't know ahead of time which robot is on the left and which is on the right.