Golfing for Domino Day

C# 1048 907 850bytes

Now heavily golfed, pretty much just a jumble of bit operations on a two-dimensional array of integer enums. Could probably be made somewhat shorter by using a 1-dimensional array, but I'm not prepared to try and re-work this at this point. Reads the dimensions and string from stdin, for example:

11 11 -\\\/|\|\-|-|\\||\-|\-|\//\//|-/-\|//|-|\-\|---||/-\//|///|||\-----|/---|-|-\--|--\/|////|//--|//-||/\-|||-/-\E||\-|\---/

Golfed:

using L=System.Console;class R{static void Main(){int p=255,e,c,E=7,D,C,X,Z,A,m=-1,t=m,f=t,u,i=t;for(;t<0;)for(t=f,f=0;(C=L.Read())>47;)f=f*10+C-48;var T=new int[f,t];for(;++i<f;)for(c=0;c<t;T[i,c++]=(C>99?68:C>91?34:C>89?112:C>87?56:C>86?131:C>80?193:C>68?7:C>67?14:C>66?28:C>64?224:C>46?136:C>44?17:0)*(C>64&C<91?1:257))C=L.Read();for(;i+E>0;E=-E)for(i=c=m;++c<f;)for(C=m;++C<t;){if(E>0&(A=D=T[c,C])>0&D<p){T[c,C]=m; X=C+(i=(D&4)>0?1:(D&64)/-64);Z=c+(u=(D&16)>0?1:D%2*m);System.Action v=()=>{if(Z>m&Z<f&X>m&X<t&&(e=T[Z,X])>p&(e>>8&A)>0)T[Z,X]&=65280|A;};v();if((i&u)!=0){X=i==u?C:X;Z=i==u?Z:c;A=((D&128)/128+D*2)&D;v();X=C+i-X+C;Z=c+u-Z+c;A=(D%2*128+D/2)&D;v();}i=8;}if(E<0&D>p&((D=D&p)&(D-1))<1&D>0)T[c,C]=D<2?131:D>64?193:D/2*7;}for(D=m;++D<f;L.WriteLine())for(c=0;c<t;L.Write(C<0?'#':(C=C>>8)>99?'/':C>67?'|':C>33?'\\':C>9?'-':' '))C=T[D,c++];}}

Because I have too much time I've modified the ungolfed version to output an animated gif of the dominoes falling (with help from this SO question and these documents 1 2). This has only added code, and it's either in a #if gifness block or clearly marked.

To create the gifs you provide a pair of command line arguments describing the frame times, output file, etc,

dominoGolf.exe console_delay (out_file_name (gif_frame_time (final_frame_time)))
dominoGolf.exe 0 outfile.gif 1 100

The third argument is the frame time for each frame (1/100s of seconds). The fourth argument is the frame time for last frame (1/100s of seconds). The second argument is the output filename for the gif. You can omit the filename, delay, and final delay if you just want the console output. The first argument is a delay between frames rendered to the terminal in milliseconds. You can omit all arguments if you don't want an animation at all and just want to see the result. It reads the domino data from stdin just like the golfed version. This code is horrible in it's own way (butchers the gif so that it loops).

Ungolfed gif-generating code:

#define gifness

using L=System.Console;

class R
{
    static void Main(string[] args) // don't need args
    {
        int p=255,P=0xFF00,m=15,M=240, // might be able to inline a couple of these
        w=1,e=2,d=4,c=8,x=16,z=32,a=64,q=128, // most of these are reusable
        W=131,E=7,D=14,C=28,X=56,Z=X*2,A=Z*2,Q=193, // most (all?) of these are reusable
        Y=w+x,U=a+d,N=c+q,B=z+e, // one of these atleast is pre-evalable

        // recognise this?
        t=-1,f=t,k,u,i=t,j,J,K,o,O,b;
        for(;t<0;)
            for(t=f,f=0;(k=L.Read())>47;)
                f=f*10+k-48;

        var T=new int[f,t]; // main arr
        // domino: dir, copy(for render)
        // motion: pickup

        // input
        for(;++i<f;) // values of i and j don't matter, just counters
        {
            for(j=0;j<t;) // increment done 3down
            {
                k=L.Read();
                T[i,j++]=(
                // fallen
                k=='W'?W:k=='E'?E:k=='D'?D:k=='C'?C:k=='X'?X:k=='Z'?Z:k=='A'?A:k=='Q'?Q:
                // dominos
                k==' '?0:k=='-'?Y:k=='/'?N:k=='|'?U:B // ASCII, order for >
                )*(k>64&k<91?1:257);
            }
        }

        #if gifness
        System.Drawing.Font font1 = null;
        System.Windows.Media.Imaging.GifBitmapEncoder genc = null;
        System.Drawing.Bitmap bmp = null;
        System.Drawing.Graphics g = null;
        if (args.Length > 1)
        {
            font1 = new System.Drawing.Font(System.Drawing.FontFamily.GenericMonospace, 12, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Pixel);
            genc = new System.Windows.Media.Imaging.GifBitmapEncoder();
            bmp = new System.Drawing.Bitmap(t * 8, f * 14); // I have no clue what these should be in relation to em size
            g = System.Drawing.Graphics.FromImage(bmp);
        }
        #endif

        if (args.Length > 0) // not important
        {
            L.Clear();
        }

        // main
        for(;i>0;) // can do i=1-i and swap setting 1 for 0 to remove {}
        {

            if (args.Length > 0) // non-critical, renders the current state to the console/gif
            {
                var os="";
                for (o=0;o<f;o++) // values of i and j don't matter, just counters
                {
                    for (j=0;j<t;j++)
                    {
                        k=T[o,j];
                        os += k==0?' ':k<p?'#':(k=k>>8)==Y?'-':k==N?'/':k==U?'|':'\\'; // order for >
                    }
                    os+="\n";
                }
                L.SetCursorPosition(0, 0);
                L.Write(os);

                #if gifness
                if (args.Length > 1)
                {
                    g.Clear(System.Drawing.Color.White);
                    g.DrawString(os, font1, System.Drawing.Brushes.Black, 0, 0);
                    System.IO.MemoryStream bms = new System.IO.MemoryStream();
                    bmp.Save(bms, System.Drawing.Imaging.ImageFormat.Gif);
                    var bmpf = System.Windows.Media.Imaging.BitmapFrame.Create(bms);
                    genc.Frames.Add(bmpf);

                    // do I chose the frame duraton1??!?!?! (take from args[2] is present else args[0])
                }
                #endif

                System.Threading.Thread.Sleep(int.Parse(args[0]));
            }

            // back to important stuff
            i=0; // set me to 1 if we do anything (8 in golfed version due to E being 7)

            // move motions
            for (j=0;j<f;j++) // careful!!
            {
                for (k=0;k<t;k++) // careful!!
                {
                    O=o=T[j,k];
                    if (o>0&o<p) // we are motion
                    {
                        T[j,k]=-1; // do this so we can't skip it

                        K=k+(i=((o&d)>1?1:(o&a)>0?-1:0));
                        J=j+(u=((o&x)>1?1:(o&w)>0?-1:0));

                        System.Action v=()=>{
                            if(J>=0&J<f&K>=0&K<t&&(b=T[J,K])>p&&((b>>8)&O)>0)
                            {
                                T[J,K]&=(P|O);
                            }
                        };

                        v();
                        if (i!=0&u!=0)
                        {
                            K=i==u?k:K; // k+i == K
                            J=i==u?J:j; // j+u == J
                            O=(((o&q)>0?w:0)+o*2)&o;
                            v();

                            K=K==k?k+i:k;
                            J=J==j?j+u:j;
                            O=(((o&w)>0?q:0)+o/2)&o;
                            v();
                        }

                        i=1;
                    }
                }
            }

            // move dominos
            for (j=0;j<f;j++) // careful!!
            {
                for (k=0;k<t;k++) // careful!!
                {
                    o=T[j,k];
                    if (o>p) // we are domino
                    {
                        o=o&p;
                        if ((o&m)<1!=(o&M)<1)
                        { // we have motion
                            T[j,k]=o==w?W:o==q?Q:o+o/2+o*2;
                        }
                    }
                }
            }
        }

        if (args.Length > 0)
        {
            L.SetCursorPosition(0, 0);
        }

        // output
        for (o=0;o<f;o++)
        {
            for (j=0;j<t;j++)
            {
                k=T[o,j];
                L.Write(k<0?'#':(k=k>>8)==0?' ':k==Y?'-':k==N?'/':k==U?'|':'\\'); // order for >
            }
            L.WriteLine();
        }


        #if gifness
        if (args.Length > 1)
        {
            g.Dispose();
            bmp.Dispose();

            System.IO.MemoryStream ms = new System.IO.MemoryStream();

            genc.Save(ms);
            byte[] data = ms.GetBuffer();
            byte[] netscape = { 0x21, 0xFF, 0x0B, 0x4E, 0x45, 0x54, 0x53, 0x43, 0x41, 0x50, 0x45, 0x32, 0x2E, 0x30, 0x03, 0x01, 0x00, 0x00, 0x00 };

            if (args.Length > 2)
            {
                int last = -1;
                int duration = int.Parse(args[2]);

                // promise yourself now you will never use this in production code
                // I've not read enough of the GIF spec to know if this is a bad idea or not
                for (i = 0; i < ms.Length - 5; i++)
                {
                    if (data[i] == 0x21 && data[i+1] == 0xF9 && data[i+2] == 0x04 && data[i+3] == 01)
                    {
                        data[i+4] = (byte)(duration & p); // something endian (least significant first)
                        data[i+5] = (byte)((duration & P) >> 8);
                        last = i+4;
                    }
                }

                if (last != -1 && args.Length > 3)
                {
                    duration = int.Parse(args[3]);
                    data[last] = (byte)(duration & p);
                    data[last+1] = (byte)((duration & P) >> 8);
                }
            }

            using (System.IO.FileStream fs = new System.IO.FileStream(args[1], System.IO.FileMode.Create))
            {
                fs.Write(data, 0, 13);

                // behold
                fs.Write(netscape, 0, netscape.Length);

                fs.Write(data, 13, (int)ms.Length - 13); // lets hope these arn't in excess of 2GBs
            }
        }
        #endif
    }
}

An example gif for the 3rd example input (and that shown above)

3rd example

Example randomly generated 100x25 domino layout

100x25 domino layout

"Domino" in dominoes

"Domino" in dominoes


Python 1188

Basically just loops through continuously matching some hefty regex until it stops changing. It actually matches all the pushes of each direction separately (through regex), and then composes the different results making sure there are no conflicts and such.

The regex can probably be done much more compactly, but for now here is what I have (it assumes the grid is stored in a string, g, and the dimensions are in x and y):

import re;L='QWEADZXC';a='';m=(x*y+y);o=[0]*m;X='(.{%s})';t=X%x;u=X%(x+1);v=X%(x-1);R=range
def S(s,l):
 f=s
 for p,r in l:
    n=re.sub(p,r,s,flags=re.DOTALL)
    for i in R(len(n)):
     if n[i]!=s[i]:f=f[:i]+n[i]+f[i+1:]
 return f
while g != a:
 a=g;n='';d=[S(g,[(r'D\|','DD'),(r'D\\','DE'),('D/','DC')]),S(g,[(r'\|A','AA'),(r'\\A','ZA'),('/A','QA')]),S(g,[('-%sW'%t,r'W\1W'),(r'\\%sW'%t,r'E\1W'),('/%sW'%t,r'Q\1W')]),S(g,[('X%s-'%t,r'X\1X'),(r'X%s\\'%t,r'X\1Z'),(r'X%s/'%t,r'X\1C')]),S(g,[('C%s/'%u,r'C\1C'),('C%s-'%u,r'C\1X'),(r'C%s\|'%u,r'C\1D'),('C%s/'%t,r'C\1C'),('C%s-'%t,r'C\1X'),('C/','CC'),(r'C\|','CD')]),S(g,[(r'Z%s\\'%v,r'Z\1Z'),('Z%s-'%v,r'Z\1X'),(r'Z%s\|'%v,r'Z\1A'),(r'Z%s\\'%t,r'Z\1Z'),('Z%s-'%t,r'Z\1X'),(r'\\Z','ZZ'),(r'\|Z','AZ')]),S(g,[('/%sQ'%u,r'Q\1Q'),('-%sQ'%u,r'W\1Q'),(r'\|%sQ'%u,r'A\1Q'),('/%sQ'%t,r'Q\1Q'),('-%sQ'%t,r'W\1Q'),('/Q','QQ'),(r'\|Q','AQ')]),S(g,[(r'\\%sE'%v,r'E\1E'),('-%sE'%v,r'W\1E'),(r'\|%sE'%v,r'D\1E'),(r'\\%sE'%t,r'E\1E'),('-%sE'%t,r'W\1E'),(r'E\\','EE'),(r'E\|','ED')])]
 for i in range(m):
    c=0
    for r in d:
     if r[i]in L:
        if c==0:c=r[i]
        elif r[i]!=c:o[i]=1;break
    n+=g[i]if c==0 or o[i]else c
 g=n
print re.sub(r'\w','#',g)

More ungolfed:

import re

L = 'QWEADZXC'

def sub_all(string,lst):
    final = string
    for p,r in lst:
        new = re.sub(p,r,string,flags=re.DOTALL)
        for i in range(len(new)):
            if new[i]!=string[i]:
                final=final[:i]+new[i]+final[i+1:]
    return final

def dominoes(grid,x,y):
    print len(grid),x*y+y
    print grid
    
    last = ''
    locked = [0]*(x*y+y)
    while grid != last:
        last = grid
        
        Dgrid = sub_all(grid,[(r'D\|','DD'),(r'D\\','DE'),('D/','DC')])
        Agrid = sub_all(grid,[(r'\|A','AA'),(r'\\A','ZA'),('/A','QA')])
        Wgrid = sub_all(grid,[('-(.{%s})W'%x,r'W\1W'),(r'\\(.{%s})W'%x,r'E\1W'),('/(.{%s})W'%x,r'Q\1W')])
        Xgrid = sub_all(grid,[('X(.{%s})-'%x,r'X\1X'),(r'X(.{%s})\\'%x,r'X\1Z'),(r'X(.{%s})/'%x,r'X\1C')])
        
        Cgrid = sub_all(grid,[('C(.{%s})/'%(x+1),r'C\1C'),('C(.{%s})-'%(x+1),r'C\1X'),(r'C(.{%s})\|'%(x+1),r'C\1D'),
                        ('C(.{%s})/'%x,r'C\1C'),('C(.{%s})-'%x,r'C\1X'),
                        ('C/','CC'),(r'C\|','CD')])
        
        Zgrid = sub_all(grid,[(r'Z(.{%s})\\'%(x-1),r'Z\1Z'),('Z(.{%s})-'%(x-1),r'Z\1X'),(r'Z(.{%s})\|'%(x-1),r'Z\1A'),
                        (r'Z(.{%s})\\'%x,r'Z\1Z'),('Z(.{%s})-'%x,r'Z\1X'),
                        (r'\\Z','ZZ'),(r'\|Z','AZ')])
        
        Qgrid = sub_all(grid,[('/(.{%s})Q'%(x+1),r'Q\1Q'),('-(.{%s})Q'%(x+1),r'W\1Q'),(r'\|(.{%s})Q'%(x+1),r'A\1Q'),
                        ('/(.{%s})Q'%x,r'Q\1Q'),('-(.{%s})Q'%x,r'W\1Q'),
                        ('/Q','QQ'),(r'\|Q','AQ')])
        
        Egrid = sub_all(grid,[(r'\\(.{%s})E'%(x-1),r'E\1E'),('-(.{%s})E'%(x-1),r'W\1E'),(r'\|(.{%s})E'%(x-1),r'D\1E'),
                        (r'\\(.{%s})E'%x,r'E\1E'),('-(.{%s})E'%x,r'W\1E'),
                        (r'E\\','EE'),(r'E\|','ED')])
        
        grids = [Dgrid,Agrid,Wgrid,Xgrid,Cgrid,Zgrid,Qgrid,Egrid]
        ngrid = ''
        
        for i in range(x*y+y):
            c = None
            for g in grids:
                if g[i] in L:
                    if c==None: c = g[i]
                    elif g[i] != c:
                        ngrid += grid[i]
                        locked[i]=1
                        break
            else:
                ngrid += grid[i] if c==None or locked[i] else c
        grid = ngrid
        print grid
    return re.sub(r'\w','#',grid)

The listed inputs all produce their outputs except the third, in which I'm pretty sure there's a mistake (the \-/ at the very top should be \|/ if the given output is desired). I'm also assuming that the . in the bottom left corner of the last one was intended to be a D.