1D Chess

(rowan441.github.io)

213 points | by burnt-resistor 2 hours ago

25 comments

  • hackyhacky 11 minutes ago
    If you enjoyed this, you might like Mind Chess, which can be played without a board and pieces [1]:

    Consider Mind Chess. Two players face each other. One says "Check." The other says "Check." The first says "Check." This continues until one of them says, instead, "Checkmate." That player wins -- superficially. In fact, the challenge is to put off checkmate for as long as possible, while still winning. This may be better stated: you truly win Mind Chess if you call "Checkmate" just before your opponent was about to.

    [1] http://www.eblong.com/zarf/essays/mindgame.html

  • quuxplusone 1 hour ago
    Mentioned in TFA: This version of chess is given by Martin Gardner in his "Mathematical Games" column of July 1980 (pages 27 and 31) — https://www.jstor.org/stable/24966361 — and the analysis of White's mate is given in the column of August 1980 (page 18) — https://www.jstor.org/stable/24966383.

    I do wonder how things would change if the board were 9 cells long; 10 cells long; etc. Also, it seems "in the spirit" to permit castling if neither K nor R has moved yet: i.e., from the position

    K _ R N r _ n k

    White ought to be permitted to

    _ R K N r _ n k

    (Or maybe there's a stronger argument for R K _ N r _ n k, actually. The former was conceptually "rook moves halfway toward king, then king moves to the other side of rook"; but the latter is "rook moves two steps in king's direction while king moves to the other side of rook.")

    I'm pretty sure this wouldn't change the analysis on the 8-cell board at all, though. I wonder if it would change the analysis on any size of board.

    • al_borland 42 minutes ago
      Maybe I'm not good enough at chess to understand the strategy here, but how would castling be useful in this 1-D game? Castling in a normal game protects your King and activates the Rook. In this 1-D game, your King starts out protected behind the Rook. If you castle and end up in a _ R K N position, your king is exposed and your Rook is trapped behind the King, useless, with no way to ever get it back out. The Rook seems essential for mate, and its power has been eliminated.
  • juleiie 38 minutes ago
    That finally confirmed that I am too regarded for chess if even 1D is too hard yay
    • amrrs 22 minutes ago
      is that str.replace(g,t) ?
  • asibahi 1 hour ago
    This is really nice.

    Incidentally, there is an actual 1D game that is one of the most popular games on the planet: Backgammon.

    • zniturah 54 minutes ago
      Good observation. Considering stacking of pieces maybe 1.5D though.
      • a3w 11 minutes ago
        Chess has different pieces, which has higher entropy than a true 1d backgammon or 1d checkers with only one piece a field.

        You could play with pieces that have a value of 1..N instead. Starting with 2,3, and 5 value pieces, and splitting them as needed. Making it one-dimensional again, while keeping 100% of the rules.

        Final verdict, therefore: backgammon is 1D, not 1.5.

        We could pretend that the second dimension was not playing a role in tactics back then, since it was very recently invented, like the brothers Wright invented the third dimension a hundred years ago. Or some hot air balloon at a world faire did it.

    • etskinner 10 minutes ago
      Mancala is roughly 1D too!
    • moffkalast 46 minutes ago
      Backgammon, the game everyone's seen and at the same time nobody knows how to play :P
      • Sharlin 4 minutes ago
        I learned to play backgammon because it was one of the three games on my Nokia phone circa 2001 :P
  • gef 1 hour ago
    Reminds me of Edwin A. Abbott's Flatland, where he describes Lineland. A one-dimensional world whose King can only move forward and backward, cannot conceive of sideways, and considers his tiny segment of existence complete and sufficient. The Linelanders are portrayed as pitiable, intellectually imprisoned by their single dimension. Much like us in our three :)
  • hart_russell 15 minutes ago
    I don’t know why this is stalemate: N4 N5, N6 K7, R5. Wouldn’t rook have the king in checkmate?
    • Scarblac 13 minutes ago
      The rook doesnt attack the king because N6 is in the way.

      So black is not in check and has no legal moves, so stalemate.

    • _air 13 minutes ago
      Black has no legal moves because of the knight but they aren't in check
  • darepublic 16 minutes ago
    I won after four attempts. Pretty sure it was perfect play so yes white has forced win
  • palata 1 hour ago
    It was a lot more fun than I first thought!
  • sieste 1 hour ago
    It took me an embarrassing number of attempts to win.
  • tempestn 19 minutes ago
    That's actually a fun little puzzle.
  • northfield27 1 hour ago
    Haha, i was taking N4 and N6, but didn’t figure the steps after that.

    To win we need to let knight die because rook can move multiple steps to kill the king.

    From a third person perspective R2 is a deceptive move that takes advantage algorithm to make the black king back off to kill its knight.

    • aNapierkowski 32 minutes ago
      you could also just move your king on that move same result knight cant move, only king can, so it has to back away
  • kkaske 1 hour ago
    I was only able to beat this after a couple retries. The hint was hard to read.
  • sjdv1982 10 minutes ago
    Zugzwang!
  • bbx 1 hour ago
    Oh very interesting. Even with these restrictions, there are quite a few variations, and it seems only one ends up with white winning.
  • schmeichel 1 hour ago
    Finally, a version of Chess I can understand. Thank you.
  • addybojangles 32 minutes ago
    Silly nice brain teaser
  • rOOmbambar9 1 hour ago
    It's very interesting and fun!)
  • lschueller 1 hour ago
    Cool idea. This is smart and lean. I like it
  • BiraIgnacio 23 minutes ago
    love it!
  • tkapin 2 hours ago
    Nice! :)
  • vladde 1 hour ago
    i could not beat it, and i can't read that chess notation
    • thesuitonym 1 hour ago
      The letter is the piece to move, and the number is the index to move to, starting from 1 on the left. The first alphanumeric pair is your move, then the computer's move. Comma. Your move, computer's move...
    • qup 1 hour ago
      The first move after the comma is yours (open with kNight to 4), and the second move is apparently predetermined or always chosen.
    • burnt-resistor 13 minutes ago
      There's a coordinate-based solution in the source code issues. I couldn't elucidate that notation either.

      https://github.com/Rowan441/1d-chess/issues/1

      Edit: There's a second solution where instead of moving the rook back 2, move the king forward one and the take the black knight with the rook as the checkmate move.

    • DrammBA 1 hour ago
      the notation is just an array of move tuples, each tuple contains 1 move for white and 1 move for black, where each move is written as <1st letter of piece name><destination square>
  • naorz 2 hours ago
    Fun stuff, love it!
  • tintor 1 hour ago
    The first move is always: white rook takes black rook, then the only remaining move for black is to move the knight away, which results in checkmate.
    • nippoo 1 hour ago
      If you play the game, you realise this ends up in stalemate.
      • Fabricio20 46 minutes ago
        I'm not very good at chess, but I dont get why most things are considered a stalemate? I strategically remove all pieces of the enemy, leaving only the king against my rook/tower whatever its called, the king has nowhere to run. In my eyes it's a checkmate. The game just calls it a stalemate. Would be a stalemate if I couldn't do anything, but I can kill the enemy king.
        • al_borland 36 minutes ago
          It's a stalemate because while the king can't move, he isn't under active attack. There is nowhere he can legally move, but he's safe where he's at.
        • rokkamokka 36 minutes ago
          There is an explanation further down. A stalemate is if the enemy has no valid loves and is not in check
    • umanwizard 54 minutes ago
      Black can’t move the knight: it’s illegal to make a move that puts yourself in check. Thus black has no legal moves, but isn’t in check, so the result is a draw.