The emperor’s troops have captured you, the leader, and your 8 soldiers. He says he will execute you all but has given you the chance to take his challenge.
The emperor says that you and your platoon will be free if you survive his challenge, else, you will all die.
The emperor says that he will drug you and your 8 soldiers and put you all in the middle of a dry desert at a crossroads. There are 4 paths – one North, one East, one South, and one West, each which takes 8 hours to walk. One of the paths leads to a village that, if you find, ensures your freedom. When you all wake up, you may lead your soldiers to freedom.
You accept the challenge.
Before the emperor drugs you and your soldiers, he offers his advice. One should not wander off the paths, for if they do, they will surely get lost and die and furthermore you and your soldiers only have a day, 24 hours, to find the correct path to the village. Any more time in the desert and you all will die from thirst and hunger.
When you wake up in the desert you find a note in your pocket from the emperor. It reads: “I forgot to mention – two of your soldiers are my spies. They may or may not lie to you, but it is in their best interest to prevent you from reaching the village. The spies are peaceful, so they will not hurt you or your soldiers.”
As you fold the note up and tuck it away, your soldiers begin to wake up and the challenge begins.
Reaching the village in 24 hours is possible without trickery (digging for water, finding and oasis, having the spies tell you where the village is) and without anyone dying. The emperor has not tried to trick you in anyway either.
You must depend on your logic and reasoning. What is your solution?
Split into 4 groups: 2 groups of 3, 1 group of 2 and you. All go in separate directions and return to the starting point in 16 hours.
The trick is to determine who are the spies. Remember that they will not always lie.
If you find the village, take the same path again.
If you did not find the village and everyone in the 2 groups of 3 also report that they did not find the village, then it is down the path with the group of 2 men and they are both spies.
If only one of the groups of 3 has one man who say that the village is there, then he is right and the other two men are spies.
If both groups of 3 are in disagreement, then the majority vote wins. Each group of 3 has 1 spy each.
If the group of 2 is in disagreement and of the groups of 3 is also in disagreement, then we can trust the majority in the group of 3. If it’s not in the path of either of the groups of 3 men, then take the path with the two in disagreement.