Solve puzzle 12 part 2

1 files changed, 18 insertions, 2 deletions

diff --git a/12.c b/12.c
index 417ebdb..10dc461 100644
--- a/12.c
+++ b/12.c
@@ -2,6 +2,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 
 
 struct pos {
@@ -86,14 +87,26 @@ tryvisit(unsigned char * range, int cols, int rows, struct pos const * from, int
 
 
 int
-main()
+main(int argc, char ** argv)
 {
+	int part = 1;
 	unsigned char * range, * p;
 	size_t rangesize, rangelen, bytes;
 	int cols, rows;
 	struct pos * front;
 	int steps;
 
+	while ((steps = getopt(argc, argv, "p:")) != -1) {
+		switch (steps) {
+		case 'p':
+			part = atoi(optarg);
+			break;
+
+		default:
+			return -1;
+		}
+	}
+
 	// Read hill range
 	rangesize = BUFSIZ;
 	rangelen = 0;
@@ -141,9 +154,12 @@ main()
 		struct pos * loc;
 
 		for (loc = front; loc != NULL; loc = loc->next) {
-			if ((range[loc->x + loc->y * cols] & 0x7F) == 'S')
+			if (part == 1 && (range[loc->x + loc->y * cols] & 0x7F) == 'S')
 				// We found the start point!
 				break;
+			if (part == 2 && height(range[loc->x + loc->y * cols]) == 'a')
+				// We found a low point
+				break;
 
 			if (tryvisit(range, cols, rows, loc, -1, 0))
 				nextfront = pos_create(loc->x - 1, loc->y, nextfront);