memorize the double-room check on day two

2021-12-12 13:05:45 -05:00 · 2021-12-12 13:05:45 -05:00 · c2a087abf7
commit c2a087abf7
parent 6fe9d251bd
1 changed files with 2 additions and 1 deletions
--- a/12/main.go
+++ b/12/main.go
@ -77,7 +77,8 @@ func descend(rooms map[string]room, currentRoom string, path []string, success c
 			wg.Add(1)
 			go func(link string, path []string) {
 				defer wg.Done()
-				descend(rooms, link, path, success, canVisitSmallRoomTwice)
+				// in day 2, skip checks once we know we've visited a small room twice
+				descend(rooms, link, path, success, canVisitSmallRoomTwice && !doubleSmallAlready(newPath))
 			}(link, newPath)
 		}
 	}