Generalizing the algorithm for domino tiling?

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孤独总比滥情好
孤独总比滥情好 2020-12-14 01:43

In this earlier question the OP asked the following problem:

Given a rectangular grid where some squares are empty and some are fille

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  •  情歌与酒
    2020-12-14 02:05

    1x3 tiles are hard by reduction from cubic planar monotone One-in-three 3SAT. We have to build some "circuitry" to encode the formula.

    "Gates":


    X********Y
    

    Forces exactly one of X and Y to be covered externally. Used to link a variable and its negation.


    Y***
       *
       *
      ooo  ****
      * *  *  *
      * *  *  *
      X ****  Z
    

    Forces none or all of X and Y and Z to be covered externally. Used to copy X or destroy three copies of the same thing. Wires can be shaped more or less arbitrarily using length-3 L pieces.


    *******************
    *        *        *
    *        *        *
    X        Y        Z
    

    Forces exactly one of X and Y and Z to be covered externally. One for each clause.

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