commit dd201caa137401da6f0bd386d710bf836b53564b
parent 12ca48593a4383593727c269f59f717afb6a87da
Author: Martin Ashby <martin@ashbysoft.com>
Date: Fri, 9 Dec 2022 12:16:58 +0000
day9
Diffstat:
5 files changed, 2078 insertions(+), 0 deletions(-)
diff --git a/input/day9.txt b/input/day9.txt
@@ -0,0 +1,2000 @@
+U 1
+L 2
+U 2
+D 2
+L 2
+U 1
+D 1
+U 2
+D 1
+U 2
+D 1
+R 2
+U 2
+L 1
+U 2
+D 2
+R 1
+U 1
+R 2
+L 1
+R 2
+D 2
+R 2
+D 2
+U 1
+R 1
+D 2
+L 2
+D 1
+R 2
+D 2
+R 1
+L 2
+R 1
+L 2
+R 1
+U 1
+D 2
+L 1
+D 1
+R 1
+U 1
+D 2
+L 1
+U 1
+L 2
+R 1
+D 2
+U 1
+L 1
+D 1
+L 1
+R 2
+D 1
+L 1
+R 1
+L 2
+D 2
+U 2
+D 1
+R 2
+U 1
+L 1
+U 2
+L 1
+U 2
+R 2
+U 1
+D 1
+L 2
+R 2
+D 2
+L 1
+D 2
+R 2
+D 1
+L 1
+D 2
+L 1
+R 1
+L 1
+R 2
+U 1
+R 1
+D 1
+R 1
+D 2
+R 2
+D 2
+U 1
+L 1
+D 1
+R 1
+L 2
+D 1
+U 2
+D 1
+R 1
+D 2
+U 2
+D 1
+R 1
+D 1
+R 1
+U 2
+L 1
+U 1
+R 1
+L 2
+R 1
+L 1
+D 2
+L 2
+R 1
+D 3
+L 3
+U 1
+R 2
+U 1
+R 2
+L 1
+D 1
+L 3
+U 2
+L 3
+D 1
+U 2
+L 3
+U 1
+R 2
+L 1
+R 1
+L 2
+D 2
+R 3
+L 1
+U 1
+L 1
+R 1
+U 1
+D 3
+L 3
+D 2
+R 2
+L 2
+D 1
+U 2
+L 2
+U 1
+R 3
+D 3
+L 3
+R 2
+D 3
+L 3
+U 1
+D 3
+L 2
+R 2
+D 3
+R 2
+L 1
+U 3
+D 2
+R 2
+D 3
+U 1
+D 3
+R 3
+D 2
+U 1
+L 2
+D 2
+U 2
+R 1
+L 3
+U 2
+R 2
+U 1
+R 2
+D 1
+R 2
+D 3
+U 1
+L 1
+U 2
+L 1
+D 2
+R 1
+U 1
+D 1
+R 3
+U 3
+R 1
+U 1
+L 3
+D 2
+R 2
+U 1
+R 2
+D 2
+R 3
+L 2
+U 2
+R 1
+L 3
+U 2
+R 1
+D 3
+L 2
+U 2
+R 3
+U 3
+L 1
+R 3
+D 3
+L 2
+R 3
+D 2
+R 3
+U 3
+R 1
+U 2
+D 4
+L 3
+D 2
+L 4
+R 2
+D 4
+L 1
+R 3
+L 1
+D 4
+U 4
+D 1
+R 4
+U 2
+D 2
+R 1
+U 2
+D 1
+L 3
+D 2
+U 2
+L 1
+R 3
+L 3
+U 3
+L 2
+R 1
+D 2
+R 3
+L 2
+D 4
+U 2
+L 3
+R 3
+L 3
+U 4
+D 4
+L 1
+U 3
+R 4
+L 4
+D 4
+U 3
+R 4
+L 2
+D 1
+U 1
+L 4
+D 3
+U 3
+R 2
+D 3
+U 4
+L 2
+R 1
+L 2
+R 2
+U 3
+L 1
+D 4
+U 1
+L 4
+R 3
+L 3
+R 2
+D 4
+U 4
+L 4
+D 3
+R 1
+D 3
+R 4
+L 4
+R 2
+L 2
+D 2
+R 2
+L 2
+U 3
+R 3
+D 2
+R 4
+L 1
+R 2
+U 4
+L 2
+R 1
+U 2
+R 3
+D 2
+U 1
+R 4
+L 3
+U 3
+D 4
+U 1
+L 1
+R 1
+D 2
+R 1
+D 1
+L 2
+D 4
+U 4
+L 4
+U 3
+D 4
+U 4
+D 3
+U 3
+L 5
+U 4
+L 4
+U 5
+D 1
+L 5
+U 2
+D 4
+U 5
+L 4
+U 2
+D 4
+R 3
+L 5
+U 2
+L 1
+U 5
+L 4
+D 2
+U 5
+R 3
+D 2
+U 3
+L 3
+R 3
+D 5
+U 4
+D 5
+U 4
+R 1
+L 1
+U 3
+L 3
+R 4
+L 1
+U 2
+D 3
+U 5
+L 3
+R 5
+D 3
+U 4
+L 1
+U 3
+R 2
+L 2
+U 5
+D 3
+L 5
+D 1
+R 3
+L 5
+R 1
+D 2
+U 3
+D 2
+L 4
+D 4
+R 5
+L 5
+U 1
+L 5
+R 3
+L 3
+U 4
+R 3
+L 3
+R 1
+L 2
+D 1
+U 3
+L 5
+R 1
+L 5
+U 3
+R 4
+U 4
+D 3
+U 2
+L 5
+D 3
+L 3
+R 2
+D 2
+U 3
+D 3
+R 2
+D 3
+L 1
+R 1
+U 1
+L 3
+R 2
+U 3
+R 1
+D 5
+U 5
+L 5
+D 2
+U 4
+D 3
+U 3
+L 4
+D 3
+U 2
+R 1
+D 4
+L 3
+U 5
+D 2
+L 5
+R 4
+D 3
+L 4
+D 3
+R 4
+D 5
+R 2
+L 3
+D 5
+U 3
+R 4
+U 6
+L 5
+D 3
+U 4
+L 1
+U 5
+R 5
+D 3
+U 5
+D 5
+R 2
+D 2
+U 4
+D 2
+U 3
+R 6
+U 4
+L 2
+R 2
+U 3
+L 1
+U 5
+R 6
+L 1
+D 5
+R 5
+D 5
+L 2
+U 3
+L 4
+R 2
+U 3
+L 2
+U 2
+D 4
+L 4
+R 5
+L 6
+D 2
+L 4
+R 2
+D 4
+L 1
+D 6
+R 2
+U 5
+D 2
+L 6
+U 5
+L 4
+U 1
+D 3
+U 1
+L 5
+U 2
+R 6
+D 5
+U 4
+L 5
+U 1
+L 5
+U 2
+R 5
+U 2
+R 4
+D 4
+R 1
+D 6
+R 5
+L 5
+U 6
+D 2
+R 1
+L 4
+U 3
+D 6
+R 4
+L 3
+R 6
+U 2
+R 1
+U 4
+R 5
+U 1
+D 4
+U 1
+L 3
+D 2
+L 2
+D 2
+L 2
+U 6
+D 4
+L 5
+D 2
+U 1
+L 5
+D 2
+R 3
+L 2
+D 2
+U 4
+L 4
+U 6
+L 1
+R 7
+L 4
+U 1
+L 1
+U 6
+L 1
+D 2
+L 5
+R 3
+U 6
+L 6
+U 2
+D 4
+L 2
+R 6
+L 3
+D 4
+L 1
+R 6
+D 4
+U 2
+D 4
+R 2
+D 1
+U 3
+R 6
+U 4
+D 2
+L 6
+R 5
+L 3
+U 1
+L 3
+U 3
+L 7
+R 1
+L 4
+D 5
+U 6
+L 3
+U 2
+L 1
+D 2
+R 4
+D 7
+R 1
+D 5
+L 1
+D 2
+U 2
+R 1
+L 1
+U 2
+D 2
+R 4
+D 7
+L 7
+D 1
+L 4
+R 7
+U 3
+L 4
+R 3
+U 2
+R 5
+U 5
+L 5
+U 2
+L 7
+R 4
+U 2
+L 5
+R 4
+U 7
+L 7
+R 5
+L 6
+D 4
+L 1
+D 6
+L 5
+R 5
+L 7
+R 5
+D 4
+U 4
+L 5
+U 7
+D 6
+U 3
+L 5
+U 4
+D 1
+L 1
+D 7
+R 3
+D 7
+U 3
+D 7
+R 4
+U 5
+L 7
+R 4
+L 5
+R 1
+D 4
+L 3
+U 1
+R 3
+L 1
+U 4
+R 3
+L 5
+D 2
+R 2
+L 4
+D 4
+L 7
+R 7
+U 2
+D 7
+L 5
+U 3
+L 4
+U 7
+R 6
+D 3
+L 2
+R 7
+L 5
+U 6
+D 6
+L 2
+D 2
+L 5
+D 7
+U 5
+L 3
+D 4
+U 4
+L 4
+R 2
+D 8
+L 3
+R 2
+D 4
+L 4
+U 7
+R 8
+D 6
+R 7
+U 1
+R 6
+U 6
+R 4
+D 8
+L 3
+R 3
+D 2
+U 5
+D 8
+L 3
+D 5
+L 7
+R 5
+L 1
+D 4
+L 7
+U 7
+L 8
+D 7
+L 5
+U 3
+R 4
+U 3
+L 7
+R 8
+D 6
+R 2
+D 3
+R 1
+D 6
+U 8
+D 6
+L 2
+R 8
+D 4
+U 3
+D 5
+U 2
+L 3
+U 1
+R 7
+U 6
+D 5
+R 5
+U 4
+L 1
+D 3
+U 7
+L 8
+U 5
+D 5
+U 4
+D 3
+L 5
+D 5
+R 5
+D 3
+R 4
+U 4
+R 8
+L 4
+D 4
+L 2
+D 4
+R 7
+L 8
+R 7
+L 1
+D 3
+U 6
+R 5
+D 1
+U 4
+R 7
+U 1
+R 2
+L 8
+U 8
+D 2
+L 9
+U 9
+D 4
+U 8
+D 3
+R 1
+U 3
+D 1
+R 7
+L 2
+U 4
+L 4
+U 9
+L 7
+U 2
+L 4
+D 5
+R 8
+L 5
+R 4
+U 2
+L 5
+U 2
+D 1
+L 9
+R 5
+D 6
+U 3
+D 5
+U 2
+L 1
+R 7
+U 1
+L 7
+U 1
+L 5
+D 6
+R 6
+D 7
+U 6
+D 7
+L 7
+D 2
+L 6
+D 4
+U 7
+D 4
+L 8
+D 5
+R 7
+L 9
+D 9
+U 3
+D 2
+U 9
+R 4
+D 3
+U 9
+R 4
+D 6
+L 2
+D 1
+L 5
+U 2
+L 5
+D 1
+R 7
+L 9
+R 6
+D 8
+L 2
+R 5
+D 6
+L 9
+U 8
+R 2
+D 4
+R 5
+U 3
+D 4
+R 6
+D 5
+U 9
+D 6
+L 3
+D 6
+R 6
+D 5
+R 7
+U 5
+L 2
+U 2
+D 5
+U 4
+D 8
+R 6
+U 8
+D 2
+R 9
+U 6
+L 1
+U 6
+L 5
+U 10
+D 2
+U 6
+R 10
+L 7
+U 4
+R 2
+D 1
+U 3
+D 6
+L 10
+U 4
+L 5
+D 10
+R 1
+L 5
+R 5
+U 6
+R 1
+D 7
+L 7
+D 4
+L 4
+D 10
+U 1
+R 9
+L 7
+D 7
+L 6
+D 7
+U 7
+R 5
+L 6
+U 3
+L 1
+D 4
+L 1
+D 3
+U 10
+D 10
+L 3
+R 6
+U 4
+D 2
+L 4
+U 1
+R 9
+D 8
+U 7
+R 10
+U 10
+L 4
+U 1
+L 9
+R 7
+L 8
+R 10
+D 6
+U 1
+R 1
+D 10
+R 4
+L 6
+D 2
+U 9
+R 6
+L 4
+U 10
+R 10
+U 4
+D 8
+U 8
+L 9
+R 9
+D 7
+L 1
+D 6
+L 7
+U 4
+L 6
+R 9
+D 6
+L 5
+D 5
+L 5
+U 6
+R 1
+D 4
+R 6
+L 5
+U 9
+R 3
+D 3
+L 10
+D 6
+U 5
+D 6
+R 6
+D 7
+R 3
+D 2
+L 2
+D 9
+U 1
+D 1
+L 1
+D 3
+U 3
+R 4
+U 1
+L 9
+U 9
+R 4
+D 10
+U 2
+L 4
+U 3
+D 1
+R 10
+U 7
+R 5
+D 6
+L 2
+U 5
+L 5
+U 5
+L 4
+D 8
+R 7
+L 5
+R 6
+U 4
+L 7
+D 4
+R 9
+D 7
+R 7
+L 2
+D 8
+L 9
+D 2
+L 7
+U 10
+R 3
+U 5
+R 3
+D 9
+U 9
+D 11
+U 6
+R 3
+U 11
+D 11
+L 11
+U 6
+D 10
+R 9
+U 11
+R 6
+L 4
+R 5
+L 11
+D 9
+L 10
+R 4
+D 11
+R 2
+L 6
+R 3
+U 4
+L 10
+U 6
+D 9
+L 5
+U 3
+R 2
+U 5
+L 7
+U 1
+L 10
+U 9
+R 3
+D 5
+R 9
+U 6
+D 9
+L 6
+R 10
+D 10
+R 8
+D 7
+L 3
+D 4
+L 6
+R 2
+D 11
+U 5
+D 7
+L 1
+U 11
+L 11
+U 3
+D 2
+L 9
+R 8
+L 11
+R 2
+D 9
+U 3
+L 9
+U 6
+D 2
+L 10
+U 8
+L 5
+R 3
+U 3
+R 1
+L 7
+R 10
+L 2
+R 7
+U 5
+D 12
+L 11
+R 2
+L 10
+U 2
+D 3
+R 3
+U 6
+D 1
+L 8
+R 4
+L 5
+U 10
+R 12
+U 9
+R 12
+L 12
+R 6
+U 11
+D 1
+R 9
+U 2
+R 11
+L 1
+R 12
+U 10
+L 9
+U 12
+R 10
+U 12
+D 12
+U 2
+D 11
+L 12
+R 9
+U 3
+D 4
+L 6
+U 3
+R 10
+D 2
+U 11
+L 4
+R 11
+U 11
+R 1
+D 10
+R 6
+U 8
+L 3
+D 6
+R 1
+U 9
+L 3
+U 5
+D 4
+R 12
+U 11
+D 2
+U 10
+L 4
+D 9
+L 4
+U 10
+D 1
+R 1
+L 5
+R 2
+D 12
+R 5
+U 3
+L 11
+D 10
+L 11
+R 7
+L 10
+U 6
+R 12
+D 3
+R 10
+U 1
+L 2
+D 1
+R 1
+L 12
+U 4
+L 3
+R 6
+L 3
+D 6
+U 7
+R 10
+U 6
+D 6
+R 5
+D 10
+R 10
+D 8
+L 10
+U 11
+R 9
+L 4
+R 8
+U 1
+D 3
+U 7
+L 3
+U 10
+R 12
+U 10
+D 10
+U 9
+D 7
+R 4
+D 2
+R 9
+U 13
+R 6
+L 4
+R 9
+L 11
+U 6
+L 12
+D 9
+R 13
+L 2
+U 7
+D 10
+L 13
+D 4
+U 6
+L 8
+U 13
+R 3
+D 2
+L 3
+R 1
+U 1
+D 7
+L 5
+D 6
+R 1
+D 3
+R 5
+L 1
+D 3
+U 11
+L 1
+D 13
+R 5
+D 2
+L 8
+D 10
+R 1
+L 2
+D 2
+L 12
+R 11
+D 13
+R 7
+D 12
+L 2
+D 5
+L 9
+D 8
+L 3
+D 2
+U 4
+D 8
+R 7
+D 8
+U 8
+R 2
+U 10
+D 7
+L 9
+U 1
+L 10
+R 4
+U 1
+L 5
+R 5
+D 10
+R 2
+L 6
+R 4
+D 10
+L 7
+R 11
+L 11
+U 7
+L 1
+D 5
+U 4
+D 6
+R 4
+U 6
+D 7
+L 2
+D 1
+R 11
+U 11
+D 12
+U 4
+D 13
+R 3
+L 4
+R 3
+L 8
+R 4
+U 7
+L 2
+R 8
+L 13
+D 6
+U 11
+L 12
+U 1
+D 3
+U 7
+L 4
+R 5
+U 7
+D 1
+L 9
+U 2
+R 4
+D 9
+U 8
+R 2
+D 9
+L 8
+D 13
+U 13
+D 1
+U 9
+D 5
+L 1
+U 12
+D 2
+R 9
+L 7
+R 1
+L 3
+R 2
+D 12
+L 11
+D 4
+R 11
+U 5
+L 13
+R 2
+U 12
+L 9
+R 10
+U 3
+D 10
+R 8
+D 12
+U 6
+R 7
+D 11
+L 10
+U 14
+L 9
+U 12
+D 4
+U 3
+D 10
+R 6
+D 5
+R 1
+D 10
+U 13
+L 9
+R 7
+U 14
+D 10
+U 7
+D 13
+L 14
+D 14
+U 6
+D 14
+L 8
+R 2
+D 7
+U 14
+R 6
+L 14
+U 14
+R 6
+D 7
+R 7
+D 3
+U 10
+D 10
+R 7
+U 11
+R 3
+L 2
+R 12
+L 13
+R 3
+U 4
+D 1
+L 7
+U 9
+R 9
+U 9
+L 11
+U 7
+D 6
+R 7
+L 3
+D 5
+U 14
+R 8
+D 7
+L 6
+U 6
+R 11
+D 9
+R 6
+D 5
+L 5
+D 1
+L 10
+R 8
+L 15
+U 1
+D 14
+L 1
+R 5
+D 5
+L 3
+U 6
+R 6
+L 4
+D 3
+L 3
+D 4
+U 7
+L 10
+D 8
+R 13
+D 9
+R 15
+D 6
+U 10
+D 14
+L 10
+U 12
+D 13
+U 8
+L 13
+U 11
+D 13
+L 8
+R 12
+U 12
+D 14
+U 15
+L 1
+R 14
+U 15
+L 14
+U 4
+D 2
+L 2
+R 6
+D 15
+U 2
+R 5
+L 7
+U 8
+D 12
+R 2
+U 2
+R 11
+L 3
+U 15
+R 15
+D 1
+U 9
+R 5
+U 1
+R 15
+U 7
+D 8
+R 6
+U 7
+R 1
+U 5
+R 15
+U 9
+L 6
+U 10
+R 10
+D 2
+U 14
+D 13
+R 11
+L 14
+D 6
+U 6
+D 6
+U 10
+D 1
+U 10
+L 11
+D 13
+U 2
+L 14
+D 9
+R 14
+U 9
+L 8
+D 11
+U 3
+L 5
+U 8
+L 1
+U 12
+L 6
+R 5
+D 8
+R 5
+D 9
+U 14
+R 13
+U 6
+L 9
+R 7
+L 5
+U 9
+L 8
+D 9
+L 3
+R 4
+L 8
+D 1
+L 4
+R 6
+U 8
+L 5
+R 12
+U 7
+R 5
+D 8
+U 6
+R 11
+U 1
+D 9
+L 7
+R 10
+L 4
+R 1
+D 11
+R 1
+U 16
+L 6
+R 7
+D 3
+R 4
+U 13
+R 12
+D 1
+L 5
+D 2
+U 4
+D 11
+L 13
+D 4
+U 2
+D 14
+L 3
+U 1
+D 13
+R 14
+U 6
+R 8
+L 16
+U 9
+D 7
+U 15
+D 15
+L 11
+R 15
+L 4
+D 5
+U 3
+L 3
+D 8
+L 6
+U 15
+L 11
+R 14
+D 8
+U 10
+D 6
+R 1
+L 16
+D 16
+L 3
+U 10
+R 5
+L 16
+R 2
+U 15
+R 10
+U 11
+R 15
+D 16
+L 3
+U 15
+L 10
+R 12
+U 13
+R 3
+L 13
+D 15
+U 4
+R 8
+U 6
+L 10
+R 12
+U 1
+L 15
+D 5
+L 1
+U 9
+D 1
+R 16
+L 7
+U 13
+L 13
+U 6
+L 1
+R 14
+L 11
+U 16
+R 15
+L 10
+D 9
+R 9
+D 6
+U 16
+R 4
+U 1
+L 3
+R 16
+L 3
+U 6
+D 15
+R 13
+D 11
+U 15
+R 3
+L 15
+D 14
+U 10
+R 7
+U 4
+R 13
+L 11
+R 13
+L 11
+R 3
+L 5
+U 12
+L 9
+U 8
+D 2
+U 17
+D 3
+R 17
+U 14
+L 9
+R 10
+D 6
+L 5
+R 14
+L 8
+U 2
+D 16
+R 15
+D 12
+U 3
+L 4
+R 12
+U 16
+D 14
+L 12
+R 8
+D 4
+R 9
+U 12
+R 15
+U 6
+L 3
+D 17
+R 3
+U 6
+L 2
+R 2
+U 2
+D 17
+L 4
+R 8
+U 17
+R 16
+L 17
+U 5
+D 11
+U 8
+L 7
+U 3
+R 1
+D 15
+U 14
+L 4
+D 9
+U 15
+R 13
+L 2
+U 4
+R 17
+U 2
+L 13
+R 4
+U 8
+R 15
+U 8
+D 13
+U 10
+D 7
+U 7
+D 17
+R 16
+L 10
+U 10
+L 8
+R 9
+L 8
+R 1
+D 10
+U 17
+D 13
+U 10
+D 13
+L 14
+R 17
+D 5
+L 1
+U 17
+D 17
+L 13
+U 12
+R 10
+D 12
+R 15
+L 15
+U 11
+L 14
+D 15
+U 12
+D 7
+U 15
+L 1
+U 2
+R 18
+L 15
+U 7
+L 8
+R 3
+D 14
+R 7
+D 7
+U 6
+R 10
+L 9
+R 9
+D 17
+R 11
+D 4
+L 16
+U 12
+R 10
+L 4
+D 7
+U 18
+L 11
+U 3
+L 13
+U 5
+R 11
+D 16
+U 14
+D 1
+R 18
+D 4
+L 7
+U 2
+D 9
+L 5
+R 14
+U 18
+R 2
+U 7
+R 8
+U 9
+L 6
+R 12
+U 15
+R 1
+L 7
+D 3
+U 10
+R 5
+U 2
+L 8
+R 13
+L 14
+D 10
+L 10
+U 12
+R 5
+L 13
+D 8
+U 5
+D 17
+L 8
+D 8
+L 7
+U 5
+D 16
+R 9
+D 6
+U 11
+D 16
+U 15
+D 6
+L 4
+R 16
+D 8
+L 11
+U 13
+R 14
+L 12
+D 2
+U 16
+D 1
+L 12
+D 10
+R 1
+D 17
+L 8
+U 13
+R 10
+U 9
+D 4
+R 1
+U 17
+L 5
+D 15
+U 9
+R 15
+U 18
+L 15
+D 18
+U 15
+D 1
+L 9
+R 6
+L 15
+R 3
+D 19
+L 5
+D 10
+L 18
+D 11
+L 14
+D 11
+U 19
+D 5
+R 9
+L 18
+R 11
+D 3
+L 7
+R 4
+D 13
+L 9
+R 14
+D 14
+L 8
+U 10
+L 11
+U 4
+D 13
+R 13
+L 7
+R 7
+D 18
+U 2
+L 17
+D 16
+R 3
+U 12
+L 13
+U 5
+L 1
+U 9
+R 6
+D 14
+U 6
+R 3
+U 6
+R 7
+D 8
+U 11
+L 11
+R 7
+U 17
+D 2
+L 12
+U 18
+L 3
+U 14
+L 6
+R 10
+L 16
+U 19
+D 9
+R 13
+U 5
+R 5
+D 15
+R 1
+L 1
+U 5
+D 16
+L 5
+R 15
+L 14
+D 5
+R 9
+U 12
+L 9
+U 7
+R 16
+D 16
+R 10
+D 15
+R 16
+L 2
+U 13
+L 5
+D 19
+R 18
+D 19
+R 16
+D 12
+R 15
+D 12
+U 5
+L 3
+R 14
+D 7
+U 11
+R 10
+L 18
+D 9
+U 2
+D 19
+U 8
+D 19
+U 18
+R 11
+D 2
+R 8
+D 14
+\ No newline at end of file
diff --git a/input/day9_ex.txt b/input/day9_ex.txt
@@ -0,0 +1,8 @@
+R 4
+U 4
+L 3
+D 1
+R 4
+D 1
+L 5
+R 2
+\ No newline at end of file
diff --git a/input/day9_ex2.txt b/input/day9_ex2.txt
@@ -0,0 +1,8 @@
+R 5
+U 8
+L 8
+D 3
+R 17
+D 10
+L 25
+U 20
+\ No newline at end of file
diff --git a/src/day9.rs b/src/day9.rs
@@ -0,0 +1,56 @@
+use core::panic;
+use std::collections::HashSet;
+
+type Pt = (i32, i32);
+/**
+ * how should the tail move to catch up with the head?
+ */
+fn catchup(head: Pt, tail: Pt) -> Pt {
+ let (hx, hy) = head;
+ let (tx, ty) = tail;
+ let xdiff = hx - tx;
+ let ydiff = hy - ty;
+ // only move if we're not adjescent (incl diagonally)
+ if xdiff.abs() > 1 || ydiff.abs() > 1 {
+ // only move 1 square (x and or y) in the direction of the head
+ (tail.0 + xdiff.signum(), tail.1 + ydiff.signum())
+ } else {
+ (tail.0, tail.1)
+ }
+
+}
+pub fn run(input: String) {
+ // series of steps
+ // let mut head: Pt = (0,0);
+ // let mut tail: Pt = (0,0);
+ // let mut htrail: Vec<Pt> = Vec::new();
+ let mut rope: Vec<Pt> = (0..10).map(|_| { (0,0) as Pt}).collect();
+ let mut trail: Vec<Pt> = Vec::new();
+ for line in input.lines() {
+ let mut toks = line.split_whitespace();
+ let dir: &str = toks.next().expect("expected a direction!");
+ let reps: u32 = toks.next().expect("expected a reps!").parse().expect("reps wasn't a number!");
+ for _ in 0..reps {
+ let head = rope[0];
+ let newhead = match dir {
+ "U" => (head.0, head.1+1),
+ "D" => (head.0, head.1-1),
+ "L" => (head.0-1, head.1),
+ "R" => (head.0+1, head.1),
+ dir => panic!("unexpected direction {}", dir),
+ };
+ rope[0] = newhead;
+ for l in 1..rope.len() {
+ rope[l] = catchup(rope[l-1], rope[l]);
+ }
+ let tail = rope.last().unwrap();
+ // htrail.push(head);
+ // tail = catchup(head, tail);
+ trail.push(*tail);
+ }
+ }
+ //println!("htrail {:?}", htrail);
+ //println!("trail {:?}", trail);
+ let trailsz = trail.into_iter().collect::<HashSet<Pt>>().len();
+ println!("Day 9: {}", trailsz);
+}
+\ No newline at end of file
diff --git a/src/main.rs b/src/main.rs
@@ -8,6 +8,7 @@ mod day5;
mod day6;
mod day7;
mod day8;
+mod day9;
fn main() {
day1::run(fs::read_to_string("input/day1.txt").expect("Failed to read input file!"));
@@ -18,4 +19,5 @@ fn main() {
day6::run(fs::read_to_string("input/day6.txt").expect("Failed to read input file!"));
day7::run(fs::read_to_string("input/day7.txt").expect("Failed to read input file!"));
day8::run(fs::read_to_string("input/day8.txt").expect("Failed to read input file!"));
+ day9::run(fs::read_to_string("input/day9.txt").expect("Failed to read input file!"));
}
