17/two.c

   1 #include <stdio.h>
   2 #include <stdint.h>
   3 #include <stdbool.h>
   4
   5 enum cellstatus {inactive, active};
   6
   7 char *inp[] =
   8         {"...#.#.#"
   9         ,"..#..#.."
  10         ,"#.#.##.#"
  11         ,"###.##.."
  12         ,"#####.##"
  13         ,"#......."
  14         ,"#..#..##"
  15         ,"...##.##"
  16         };
  17
  18 #define steps 6
  19 #define xorig (sizeof(inp[0]))
  20 #define yorig (sizeof(inp)/sizeof(char *))
  21 #define xmax (xorig+steps*2)
  22 #define ymax (yorig+steps*2)
  23 #define zmax (1+steps*2)
  24 #define wmax (1+steps*2)
  25 uint16_t map[xmax*ymax*zmax*wmax] = {inactive};
  26
  27 #define mapel(x, y, z, w) map[(w)*zmax*ymax*xmax+(z)*ymax*xmax+(y)*xmax+(x)]
  28
  29 enum cellstatus oldstatus(int x, int y, int z, int w)
  30 {
  31         if(x<0 || y<0 || z<0 || w<0 || x >= xmax || y >= ymax || z >= zmax || w >= wmax)
  32                 return inactive;
  33         return (enum cellstatus)((mapel(x, y, z, w) >> 8) & 0xff);
  34 }
  35
  36 enum cellstatus newstatus(int x, int y, int z, int w)
  37 {
  38         if(x<0 || y<0 || z<0 || w<0 || x >= xmax || y >= ymax || z >= zmax || w >= wmax)
  39                 return inactive;
  40         return (enum cellstatus)(mapel(x, y, z, w) & 0xff);
  41 }
  42
  43 void step()
  44 {
  45         //Move the old to the leftmost byte
  46         for (int w = 0; w<wmax; w++)
  47                 for (int z = 0; z<zmax; z++)
  48                         for (int y = 0; y<ymax; y++)
  49                                 for (int x = 0; x<xmax; x++)
  50                                         mapel(x, y, z, w) <<= 8;
  51         //Do a step
  52         for (int w = 0; w<wmax; w++) {
  53                 for (int z = 0; z<zmax; z++) {
  54                         for (int y = 0; y<ymax; y++) {
  55                                 for (int x = 0; x<xmax; x++) {
  56                                         int count = 0;
  57                                         for (int dw = -1; dw<=1; dw++) {
  58                                                 for (int dz = -1; dz<=1; dz++) {
  59                                                         for (int dy = -1; dy<=1; dy++) {
  60                                                                 for (int dx = -1; dx<=1; dx++) {
  61                                                                         if (dx == 0 && dy == 0 && dz == 0 && dw == 0)
  62                                                                                 continue;
  63                                                                         if (oldstatus(x+dx, y+dy, z+dz, w+dw) == active)
  64                                                                                 count++;
  65                                                                 }
  66                                                         }
  67                                                 }
  68                                         }
  69                                         switch (oldstatus(x, y, z, w)) {
  70                                         case active:
  71                                                 mapel(x, y, z, w)
  72                                                         |= count == 2 || count == 3
  73                                                         ?  active : inactive;
  74                                                 break;
  75                                         case inactive:
  76                                                 mapel(x, y, z, w)
  77                                                         |= count == 3
  78                                                         ?  active : inactive;
  79                                                 break;
  80                                         }
  81                                 }
  82                         }
  83                 }
  84         }
  85 }
  86
  87 int main()
  88 {
  89         fprintf(stderr, "Total size: %ux%ux%ux%u, %u elements, %u steps\n",
  90                 xmax, ymax, zmax, wmax, xmax*ymax*zmax*wmax, steps);
  91
  92         for(int y = 0; y<yorig; y++)
  93                 for(int x = 0; x<xorig; x++)
  94                         mapel(x+steps, y+steps, steps, steps) =
  95                                 inp[y][x] == '#' ? active : inactive;
  96
  97         for(int i = 0; i<steps; i++) {
  98                 fprintf(stderr, "step: %d\n", i);
  99                 step(map);
 100         }
 101
 102         int count = 0;
 103         for(int w = 0; w<wmax; w++)
 104                 for(int z = 0; z<zmax; z++)
 105                         for(int y = 0; y<ymax; y++)
 106                                 for(int x = 0; x<xmax; x++)
 107                                         if (newstatus(x, y, z, w) == active)
 108                                                 count++;
 109
 110         printf("%d\n", count);
 111
 112         return 0;
 113 }