Initial Commit - days 01-12

day12/ex2-c.c

@@ -0,0 +1,58 @@
+/* ex2-c: Advent2020 game, day 12/game 1
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define ABS(i)	((i)>=0?(i):(-i))
+
+int main(ac, av)
+    int ac;
+    char **av;
+{
+    char line[512], command;
+    unsigned val, direction, i;
+    int x=0, y=0, wx=10, wy=1, tmp;
+
+    while (fgets(line, sizeof line, stdin)) {
+        command=*line;
+        val=atoi(line+1);
+        direction=0;
+        switch (command) {
+            case 'L':
+                direction=360-val;
+                break;
+            case 'R':
+                direction=val;
+                break;
+            case 'F':
+                for (i=0; i<val; ++i) {
+                    x+=wx;
+                    y+=wy;
+                }
+                break;
+            case 'N':
+                wy+=val;
+                break;
+            case 'E':
+                wx+=val;
+                break;
+            case 'S':
+                wy-=val;
+                break;
+            case 'W':
+                wx-=val;
+                break;
+        }
+        if (direction) {
+            for (i=90; i<=direction; i+=90) {
+                tmp=wy;
+                wy=-wx;
+                wx=tmp;
+            }
+        }
+    }
+    printf("%s : res=%d\n", *av, ABS(x)+ABS(y));
+    exit (0);
+}