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- 100 Prisoners' Names in Boxes 6 answers
The scenario is like this:
There's a room, inside the room there are 100 cards with numbers [1,100] on them (No duplications), the cards are ordered randomly.
Two persons stand outside the room, They can decide on a tactic before the following:
- One person enters the room, he can see the order, he can make one switch between places of two numbers. (e.g: (3,1,2) ---switch 3 and 1---> (1,3,2)).
- After the switch (Or not switching) the person flips the cards and exits the room. (Other than the switch, the person does not change the order)
- The second person enters the room, A number between [1,100] is called out of the void, he has 50 guesses to get that number.
A few notes:
- The cards are in a perfect line, you can't order them vertically or something like that.
- The cards are identical, There are no particular features for specific cards or something like that.
- You can't leave anything in the room (items / human parts / ...)
- The two persons have no idea about the number that will be called.
- A guess = Flips a particular card.
- This is not the same as the prisoners, Since the first person doesn't know about the number the second person is supposed to find.