4 ms·
I thought it was "How many moves in a game does it take to reach this position"
by wodenokoto 1y ago
I thought it was "How many moves in a game does it take to reach this position"
- coolness 1y agoI also thought this but OP is right: https://dev.timenote.info/de/Nenad-Petrovic https://dev.timenote.info/de/Nenad-Petrovic > In 1964 Petrović constructed a position with 218 possible moves for White.
- jmkd 1y agoSame, which also damages my personal policy of reading the link before any HN comments.
- stephenhumphrey 1y agoHuh. I also have that personal policy. Yet this time I jumped first to the comments before reading the article. I’m not certain why. Perhaps I subconsciously intuited that the ambiguity in the headline might be resolved by some of you smart people. Brains are weird; mine is, anyway.
- jl6 1y agoThe right™ order is to check the comments before the article, but to read the article before commenting.
- winternewt 1y agoI thought it was "there's no position in chess that requires more than 218 moves to reach."
- unkulunkulu 1y agoI thought “there is no chess problem that is both reachable from starting position and requires more than 218 moves to solve”
- binarymax 1y agoThere are no more than 218 ways to interpret this title
- fer 1y agoIt'll take at most 218 comments on HN to figure out the meaning of the submission title
- matheusmoreira 1y agoIt'll take at most 218 characters to express the fact I did not understand the submitted article's title.
- leoff 1y agoI seriously thought they meant "it's not possible to have a chess game with more than 218 moves"
- ojo-rojo 1y agoYeah, I'm still confused.
- fwip 1y agoThere is no reachable[1] chess position[2] at which a player has more than 218 valid moves[3] to choose from. [1] Able to happen while following the rules of chess [2] The arrangement of chess pieces on the board [3] A valid move is the motion of one piece to a place on the board, which doesn't break the rules of chess - e.g: "King to E4."
- brumar 1y agoSame. I was astonished it was remotely possible to do this.
- weinzierl 1y agoBut this an interesting problem too. More specifically is there an upper bound for the number of moves in a legal chess game?
- kevindamm 1y agoNot explicitly, but when you consider the "cannot repeat the same board layout three times" rule, the number of moves possible in a game does have a limit.
- jibal 1y agoThe 3 repetition draw rule has no bearing on the number of possible chess positions. And for the number of possible moves in a game the 50 moves with no capture or pawn move rule is a much more stringent limit. BTW, the 3 repetition rule only comes into play is one of the players invokes it ... games can legally have more than 3 repetitions, but not more than 5 repetitions.
- kevindamm 1y agoI didn't know it required a player to invoke it, I was basing the statement on chess implementations I've read (and written) where it kicks in automatically... but the 5-time limit you mention still supports my case that there's an upper limit. As long as the number of pieces remains the same, there are a finite number of arrangements for them so eventually (after a finite number of moves) a position would be repeated enough times. If a piece is captured (or converted) it resets this but still yields a finite number of new arrangements. Eventually you either cannot avoid the repetition, or a win condition is met, or a draw for insufficient material. Compare this to, say, the L game, where the number of moves is unbounded.
- jibal 1y agoYour "case" that there's a limit isn't in question ... as I said, the 50 move rule is a far more stringent limitation. And those 50 moves cannot include repetitions--they are captures and pawn moves, which are irreversible. If you read my comment that you responded to carefully, you will find that it is precise and accurate--as I said, the repetition rule has no bearing on the number of positions. This horse is dead, so I'm moving on.