Day 5: If You Give a Seed a Fertilizer

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  • morrowind@lemmy.ml
    2·
    1 year ago

    CRYSTAL

    finally solved part 2, and in just 1 second :)))

    Input = File.read("input.txt").lines

# {source, destination}
alias Map = Tuple(Range(Int64, Int64), Range(Int64, Int64))

Maps = Array(Array(Map)).new(7)
index = 1
7.times do |i| 
	a, index = get_ranges(index + 2)
	Maps << a
end

part2
# part1

def part1()
	seeds = Input[0].split(":")[1].split.map(&.to_i64)
	locs = Array(Int64).new(7)
	
	seeds.each do |seed|
		val = seed
		Maps.each do |maplist|
			maplist.each do |map|
				if map[0].includes?(val)
					val = map[1].begin + (val - map[0].begin)
					break
		end     end     end
		locs << val
	end
	puts locs.min
end

def part2()
	seeds = Input[0].split(":")[1].split.map(&.to_i64)
	seeds = seeds.in_groups_of(2, 0).map { |a| a[0]..(a[0]+a[1]) }

	found = false
	loc = 0
	until found 
		val = loc
		Maps.reverse_each do |maplist|
			maplist.each do |map|
				if map[1].includes?(val)
					val = map[0].begin + (val - map[1].begin)
					break
		end     end     end

		seeds.each { |seedrange| break if found = seedrange.includes?(val) }
		loc += 1
	end
	puts loc - 1
end

def get_ranges(index : Int) : {Array(Map), Int32}
	line = Input[index]
	ranges = [] of Map
	until line == ""
		a, b, l = line.split.map(&.to_i64)
		ranges << {b...(b+l), a...(a+l)}
		
		index += 1
		break if index == Input.size
		line = Input[index]
	end
	{ranges, index}
end