rename repo, subdir for yearly challenges

2020/day17/ex2-c.c

@@ -0,0 +1,170 @@
+/* ex1-c: Advent2020 game, day 17/game 2
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include "list.h"
+
+#define LOOPS    6
+#define MAXINIT  8
+#define SIZE     ((2*LOOPS)+MAXINIT)
+#define ZERO     (SIZE/2)
+
+#define ACTIVE   '#'
+#define INACTIVE '.'
+
+typedef struct cell {
+    char state;
+    char oldstate;
+    bool visited;                                 /* redundant ? */
+    unsigned count;                               /* active neighbors */
+    // for runs, we don't care unused cells
+    struct list_head set;                         /* current actives */
+    struct list_head viewed;                      /* current visited */
+} CELL;
+
+LIST_HEAD(qset);
+LIST_HEAD(qviewed);
+
+static CELL cube[SIZE][SIZE][SIZE][SIZE];
+
+#define CUBEZERO           cube[0][0][0][0]
+#define CUBE2X(cell)       (((cell)-&CUBEZERO)/SIZE/SIZE/SIZE)
+#define CUBE2Y(cell)       (((cell)-&CUBEZERO)/SIZE/SIZE%SIZE)
+#define CUBE2Z(cell)       (((cell)-&CUBEZERO)/SIZE%SIZE)
+#define CUBE2W(cell)       (((cell)-&CUBEZERO)%SIZE)
+
+#define HEADRESET(elt)     {                                            \
+        (elt)->next=POISON_POINTER1;(elt)->prev=POISON_POINTER1; }
+
+static void reset_cell(CELL *pcell)
+{
+    pcell->state=INACTIVE;
+    pcell->oldstate=INACTIVE;
+    pcell->visited=false;
+    pcell->count=0;
+}
+
+static void reset_cube()
+{
+    int i, j, k, l;
+
+    for (i=0; i<SIZE; ++i)
+        for (j=0; j<SIZE; ++j)
+            for (k=0; k<SIZE; ++k)
+                for (l=0; l<SIZE; ++l)
+                    reset_cell(&cube[i][j][k][l]);
+}
+
+static int count_active()
+{
+    struct list_head *p;
+    int i=0;
+
+    list_for_each(p, &qset) {
+        ++i;
+    }
+    return i;
+}
+
+static void init_row(char *line, int row)
+{
+    int i, x, y, z, w;
+    static int ncols=0;
+    CELL *pcell;
+
+    if (ncols == 0)
+        ncols=strlen(line)-1;
+    y=ZERO-ncols/2+row;
+    z=ZERO;
+    w=ZERO;
+    for (i=0; *line; ++i, ++line) {
+        x=ZERO+i-ncols/2;
+        pcell=&cube[x][y][z][w];
+        if (*line == '#') {
+            list_add(&pcell->set, &qset);
+            list_add(&pcell->viewed, &qviewed);
+            pcell->state=ACTIVE;
+            pcell->visited=1;
+        }
+    }
+}
+
+void run_life()
+{
+    struct cell *pcell, *ptmp;
+    int x, y, z, w, x1, y1, z1, w1;
+
+    /* 1) count +1 for neighbors */
+    list_for_each_entry(pcell, &qset, set) {
+        x=CUBE2X(pcell);
+        y=CUBE2Y(pcell);
+        z=CUBE2Z(pcell);
+        w=CUBE2W(pcell);
+        for (x1=x-1; x1<=x+1; x1++) {
+            for (y1=y-1; y1<=y+1; y1++) {
+                for (z1=z-1; z1<=z+1; z1++) {
+                    for (w1=w-1; w1<=w+1; w1++) {
+                        if ((x1!=x || y1!=y || z1!=z || w1!=w)) {
+                            ptmp=&cube[x1][y1][z1][w1];
+                            ++ptmp->count;
+                            if (!ptmp->visited) {
+                                list_add(&ptmp->viewed, &qviewed);
+                                ptmp->visited=1;
+                            }
+                        }
+                    }
+                }
+            }
+        }
+    }
+    list_for_each_entry_safe(pcell, ptmp, &qviewed, viewed) {
+        switch (pcell->state) {
+            case ACTIVE:
+                if (pcell->count != 2 && pcell->count != 3) {
+                    list_del(&pcell->set);
+                    pcell->state=INACTIVE;
+                    pcell->visited=0;
+                }
+                break;
+            case INACTIVE:
+                if (pcell->count == 3) {
+                    list_add(&pcell->set, &qset);
+                    pcell->state=ACTIVE;
+                    pcell->visited=1;
+                }
+                break;
+        }
+        pcell->count=0;
+        if (pcell->state == INACTIVE) {
+            pcell->visited=0;
+            list_del(&pcell->viewed);
+        }
+    }
+}
+
+int main(ac, av)
+    int ac;
+    char **av;
+{
+    char line[16];
+    int nline=0;
+
+    reset_cube();
+    INIT_LIST_HEAD(&qset);
+    INIT_LIST_HEAD(&qviewed);
+
+    while (fgets(line, sizeof line, stdin)) {
+        init_row(line, nline);
+        nline++;
+    }
+    for (int i=0; i<LOOPS; ++i)
+        run_life();
+
+    printf("%s : res=%d\n", *av, count_active());
+
+    exit (0);
+}