Brain Teasers
Knight's Trouble
Having failed to achieve his previous goal, the knight wanted to leave Breadland. However, he was captured by the king of Breadland for stepping all around in his kingdom.
The king decided to sentence the knight to death, but before that he wanted to test the knight's intelligence. The king said:
"Play a game of chess with me. You know, in my kingdom, the chessboard is 9x7. Each player has a queen on each side of the king, one is next to the king and the other is between a bishop and a knight. Also, each player has an additional pawn.
But this time the rule is changed. Each player in turn must make TWO legal moves. He can't put his king in check either after his first move or after his second move.
If you win or the game ties, I'll set you free. If I win, I'll sentence you to death immediately.
You move first."
Could the knight avoid being sentenced to death?
The king decided to sentence the knight to death, but before that he wanted to test the knight's intelligence. The king said:
"Play a game of chess with me. You know, in my kingdom, the chessboard is 9x7. Each player has a queen on each side of the king, one is next to the king and the other is between a bishop and a knight. Also, each player has an additional pawn.
But this time the rule is changed. Each player in turn must make TWO legal moves. He can't put his king in check either after his first move or after his second move.
If you win or the game ties, I'll set you free. If I win, I'll sentence you to death immediately.
You move first."
Could the knight avoid being sentenced to death?
Hint
I only asked whether or not the knight could avoid being sentenced. I didn't ask which moves must the knight make to avoid being sentenced.Answer
The answer is affirmative.Assume that the knight couldn't avoid being sentenced. This means that no matter what moves the knight made, the king could always win.
Then the knight could move one of his knights and then move back.
But then every piece would be on its original position, and it would be the king's turn to move, and the knight could win the game, which contradicts our assumption.
Hence, the knight had a strategy to guarantee at least a tie.
Note that I didn't point out what the strategy is. I only showed its existence.
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Comments
Yet another good one kiss, keep them coming
(forgot to add)
cool, I thought yes at first then second-guessed(seems to be my permanent downfall), and then, I looked at the answer and went"wait, I was right the first time around???" i thought yes ...he could avoid it because noone wins chess if there's no check, no many no many pieces are already captured (I think, but I'm not 100% sure). Anyway, I liked it, and I got it.
well, i got it, but only cause i took a guess
good teaser, pretty clever
good teaser, pretty clever
well, i got it, but only cause i took a guess
good teaser, pretty clever
good teaser, pretty clever
If no one wins, the game is tied, and the knight is still set free.
I'm sorry but I don't get the answer.
"But then every piece would be on its original position, and it would be the king's turn to move, and the knight could win the game, which contradicts our assumption."
Why could the knight win the game? What's majical about the king making a move?
"But then every piece would be on its original position, and it would be the king's turn to move, and the knight could win the game, which contradicts our assumption."
Why could the knight win the game? What's majical about the king making a move?
Symmetry.
u r confoosin all of u guys r
symetry doesn't matter as much as the fact that its putting skill in chess against eachother. with 2 queens and other rules it makes it easier to win if you have played that way before. The knight would have to play defensive to be able to win.
This teaser makes no sense? How did this even get past the editors?
I agree
You must like to play chess.
I m with u smek....no idea what is going on here.....I personally would've rejected this one
The question posed at the end of the teaser is useless, "Could the knight avoid being sentenced to death?" The answer is yes, if he wins or draws. There is no point to this teaser. Vague questions only allow vague answers.
I also like how assumptions are made as part of the solution. You can't do that! List all assumptions in the teaser.
Even assuming your assumption is correct is incorrect. Even if going second gaves the King an advantage (which is false, see below) doesn't mean he is assured a win. White has an advantage in normal chess, however, white often loses or draws.
Also, symmetry breaks down once the first piece is captured. Don't assume the King is going to sit back and play defence. With your chess rules the only thing that is clear is that the player that goes first has the advantage, because he has the option to 'pass' on his first move or to play offense.
I also like how assumptions are made as part of the solution. You can't do that! List all assumptions in the teaser.
Even assuming your assumption is correct is incorrect. Even if going second gaves the King an advantage (which is false, see below) doesn't mean he is assured a win. White has an advantage in normal chess, however, white often loses or draws.
Also, symmetry breaks down once the first piece is captured. Don't assume the King is going to sit back and play defence. With your chess rules the only thing that is clear is that the player that goes first has the advantage, because he has the option to 'pass' on his first move or to play offense.
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