advent_of_code_2022

commit 09fc897885233cca0455911979cb1e31ef19731f
parent 3afc67b9cb99a79240f14d4247eed371dbf47025
Author: Eamon Caddigan <eamon.caddigan@gmail.com>
Date:   Thu, 15 Dec 2022 20:53:23 -0800

Solution to day 12, part 2.

Diffstat:
M
src/day_12.jl
 | 
10
+++++++++-

1 file changed, 9 insertions(+), 1 deletion(-)
diff --git a/src/day_12.jl b/src/day_12.jl
@@ -68,6 +68,11 @@ function pathdist(g::AbstractGraph, v_source::CartesianIndex{2},
     pathdist(g, source_ind, dest_ind)
 end
 
+function pathdist(g::AbstractGraph, v_source::Vector{CartesianIndex{2}},
+                  v_dest::CartesianIndex{2}, heightmap::AbstractMatrix)
+    map(x->pathdist(g, x, v_dest, heightmap), v_source)
+end
+
 function part_1(input)
     heightmap, v_source, v_dest = parse_input(input)
     pathdist(makegraph(heightmap), v_source, v_dest, heightmap)
@@ -76,6 +81,9 @@ end
 @info part_1(input)
 
 function part_2(input)
-    nothing
+    heightmap, _, v_dest = parse_input(input)
+    v_source = findall(heightmap .== 0)
+    minimum(pathdist(makegraph(heightmap), v_source, v_dest, heightmap))
 end
+@assert part_2(example) == 29
 @info part_2(input)