solutions for day 16, 17, 18 19, 20

src/day_19.jl

@@ -0,0 +1,86 @@
+include(joinpath(readchomp(`git rev-parse --show-toplevel`), "aoc.jl"))
+import .Aoc: @aoc
+using Pipe: @pipe
+using Combinatorics
+
+function prepare_input(input)
+	dict = []
+	tmp = []
+	for l in input
+		l == "" && continue
+		m = match(r"--- scanner (\d+) ---", l)
+		if m != nothing
+			length(tmp) != 0 && push!(dict, tmp)
+			tmp = []
+			continue
+		end
+		push!(tmp, parse.(Int, split(l, ",")))
+	end
+	dict
+end
+
+function align(a,b, negs, distances)
+	a2 = Set(a)
+	for re in 1:6, neg in negs
+		newb = [ neg .* collect(Combinatorics.permutations(s,3))[re] for s in b ]
+		for p1 in a2, p2 in newb
+			count = 0
+			remapped = []
+			dist = p2 .- p1
+			for b2 in newb
+				to_a = b2 .- dist
+				to_a in a2 && (count += 1)
+				push!(remapped, to_a)
+			end
+			if count >= 12
+				println("match $dist")
+				push!(distances, dist)
+				return true, remapped
+			end
+		end
+	end
+	return false, []
+end
+
+function p1(input::Vector{String})
+	@info "Something is brken. This may take 5 minutes or more to get a slightly wrong result."
+	negations = [
+		[1,1,1],
+		[-1,1,1],
+		[1,-1,1],
+		[1,1,-1],
+		[-1,-1,1],
+		[-1,1,-1],
+		[-1,-1,-1],
+		[1,-1,-1]
+	]
+	list = prepare_input(input)
+	aligned_idx = Set(1)
+	aligned = Dict(1 => list[1])
+	beacons = copy(list[1])
+	dont_align = Set()
+	distances = [[0,0,0]]
+	while length(aligned_idx) < length(list)
+		for i in 1:length(list)
+			i in aligned_idx && continue
+			for j in sort(collect(aligned_idx))
+				println("checking $i against $j")
+				(i,j) in dont_align && continue
+				found, remapped = align(aligned[j], list[i], negations, distances)
+				if found
+					push!(aligned_idx, i)
+					aligned[i] = remapped
+					beacons = vcat(beacons, remapped)
+					break
+				end
+				push!(dont_align, (i,j))
+			end
+		end
+	end
+	return length(beacons)
+end
+
+function p2(input::Vector{String})
+end
+
+@aoc(2021, 19)