Reverse direction of search

1 files changed, 8 insertions, 8 deletions

diff --git a/12.c b/12.c
index 42d63d4..417ebdb 100644
--- a/12.c
+++ b/12.c
@@ -75,7 +75,7 @@ tryvisit(unsigned char * range, int cols, int rows, struct pos const * from, int
 
 	// Check height
 	src = range[from->x + from->y * cols];
-	if (height(dst) > height(src) + 1)
+	if (height(dst) < height(src) - 1)
 		return 0;
 
 	// OK. We can visit, so mark the new position as visited.
@@ -126,9 +126,9 @@ main()
 	}
 	rows = rangelen / cols;
 
-	// Find start, and mark it as visited
-	if ((p = memchr(range, 'S', rangelen)) == NULL) {
-		fprintf(stderr, "No start position!\n");
+	// Find end, and mark it as visited
+	if ((p = memchr(range, 'E', rangelen)) == NULL) {
+		fprintf(stderr, "No end position!\n");
 		free(range);
 		return -1;
 	}
@@ -141,8 +141,8 @@ main()
 		struct pos * loc;
 
 		for (loc = front; loc != NULL; loc = loc->next) {
-			if ((range[loc->x + loc->y * cols] & 0x7F) == 'E')
-				// We found the end point!
+			if ((range[loc->x + loc->y * cols] & 0x7F) == 'S')
+				// We found the start point!
 				break;
 
 			if (tryvisit(range, cols, rows, loc, -1, 0))
@@ -167,9 +167,9 @@ main()
 	}
 
 	if (front)
-		printf("Found end at %d,%d in %d steps\n", front->x, front->y, steps);
+		printf("Found start at %d,%d in %d steps\n", front->x, front->y, steps);
 	else
-		printf("No end found after %d steps\n", steps);
+		printf("No start found after %d steps\n", steps);
 
 	pos_free(front);
 	free(range);