c implementatino

diff --git a/11/one.c b/11/one.c
new file mode 100644 (file)
index 0000000..c6fb07e
--- /dev/null
+++ b/11/one.c
@@ -0,0 +1,113 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+enum cellstatus {floor, empty, occup, oob};
+
+uint16_t map1[100][100] = {oob};
+uint16_t map2[100][100] = {oob};
+int xmax, ymax;
+
+enum cellstatus seat(int x, int y, uint16_t map[100][100])
+{
+       return x < 0 || y < 0 || x >= xmax || y >= ymax ? oob
+               : (enum cellstatus)((map[x][y] >> 8) & 0xff);
+}
+
+bool lookone(int x, int y, int dx, int dy, uint16_t map[100][100])
+{
+       return seat(x+dx, y+dy, map) == occup;
+}
+
+bool looktwo(int x, int y, int dx, int dy, uint16_t map[100][100])
+{
+       enum cellstatus s;
+       while((s = seat(x += dx, y += dy, map)) == floor);
+       return s == occup;
+}
+
+bool step(bool (*lookfun)(int, int, int, int, uint16_t map[100][100]), int die, uint16_t map[100][100])
+{
+       //Move the old to the leftmost byte
+       for (int y = 0; y<ymax; y++)
+               for (int x = 0; x<xmax; x++)
+                       map[x][y] <<= 8;
+       //Do a step
+       bool same = true;
+       for (int y = 0; y<ymax; y++) {
+               for (int x = 0; x<xmax; x++) {
+                       enum cellstatus st = seat(x, y, map);
+                       if (st == floor) {
+                               map[x][y] |= floor;
+                               continue;
+                       }
+                       int count = 0;
+                       for (int dx = -1; dx<=1; dx++) {
+                               for (int dy = -1; dy<=1; dy++) {
+                                       if (dx == 0 && dy == 0)
+                                               continue;
+                                       if (lookfun(x, y, dx, dy, map))
+                                               count++;
+                               }
+                       }
+                       if (st == empty) {
+                               if (count == 0) {
+                                       same = false;
+                                       map[x][y] |= occup;
+                               } else {
+                                       map[x][y] |= empty;
+                               }
+                       } else if(st == occup) {
+                               if (count >= die) {
+                                       same = false;
+                                       map[x][y] |= empty;
+                               } else {
+                                       map[x][y] |= occup;
+                               }
+                       }
+               }
+       }
+       return same;
+}
+
+int main()
+{
+       int x = 0, y = 0;
+       int c;
+       while ((c = getchar()) != EOF) {
+               switch (c) {
+               case 'L':
+                       map1[x][y] = empty;
+                       map2[x++][y] = empty;
+                       break;
+               case '.':
+                       map1[x][y] = floor;
+                       map2[x++][y] = floor;
+                       break;
+               case '\n':
+                       xmax = x;
+                       x = 0;
+                       y++;
+                       break;
+               }
+       }
+       ymax = y;
+
+       //Do one
+       while(!step(lookone, 4, map1));
+
+       //Do two
+       while(!step(looktwo, 5, map2));
+
+       int count1 = 0, count2 = 0;
+       for (int y = 0; y<ymax; y++) {
+               for (int x = 0; x<xmax; x++) {
+                       if ((map1[x][y] & 0xff) == occup)
+                               count1++;
+                       if ((map2[x][y] & 0xff) == occup)
+                               count2++;
+               }
+       }
+       printf("one: %d, two: %d\n", count1, count2);
+       return 0;
+}