ref: 0066cdd62aea5bde96903682e7fbdadfd5fd08d9
parent: fc3f16b364e64ad01c3c1d19e99051b922e2a4f8
author: Simon Tatham <anakin@pobox.com>
date: Sun May 22 07:45:20 EDT 2005
Special case in dead-end checking which prevents the solver falling over on a grid containing a 0 (completely blank) tile. This can't happen in self-generated grids, but can happen if you type in a grid from another Net implementation. Previously, the solver would notice (technically correctly!) that a completely blank tile connects to no other tiles and thus forms an isolated subgraph, and would therefore complain that no orientation of that tile could possibly yield a valid solution... [originally from svn r5828]
--- a/net.c
+++ b/net.c
@@ -657,7 +657,7 @@
* dead ends of size 2 and 3 forms a subnetwork
* with a total area of 6, not 5.)
*/
- if (deadendtotal+1 < area)
+ if (deadendtotal > 0 && deadendtotal+1 < area)
valid = FALSE;
} else if (nnondeadends == 1) {/*