There are 4 men, each of them are stuck in the ground up to their chin and cannot turn their neck. Two of them are wearing a green hat and two are wearing a white hat. At least one of them need to figure out what order the hats are arranged on each of their heads or they will be killed... with a rusty chainsaw. They cannot speak to each other but can only blurt out the answer if they know it.
Trick is one of the men are stuck behind the wall while the other three are on the other side of the wall (again, all facing the wall) like so: (G = green hat, W = If you don't know, give up)
G> | <W <G <W
No one can see over, or through the wall. One of them can be absolutely 100% sure what order the hats are in, how?
