Consider the picture below:
In this picture, there are 4 prisoners buried in the ground. There is a brick wall separating A and B. C can see B and D can see both B and C. Between the 4 prisoners, 2 white and 2 black hats are worn. No one can see their own hat color. The hat color is fixed as shown in the picture. To survive, at least one prisoner must call out their hat color correctly. Who will call out the hat color?
- via Camworld