Smart way to freedom.
Once in a country there were these two thieves who were notorious for their intelligence. After much effort the soldiers captured them and brought them before the king. Now in this country the punishment for theft was capital, but the king being impressed by their smartness wanted to give them a chance. The thieves were bound to separate pillars facing each other and two consecutive numbers between 1 and 100 were stuck to their foreheads. One of them will be asked whether he knows the number on his forehead. If he knows, he must say what number it is, otherwise he can pass and the turn goes to the other thief (this can go on indefinitely). If the answer given is wrong, both of them will be executed by hanging. If the answer is right both will be left free.
After a few turns one of them said the correct answer.
How was it possible.