const grid::Vector{Vector{UInt8}} = [ [ UInt8(x) - UInt8('0') for x in collect(line) ] for line in readlines("input/10") ]
const size = length(grid)

isOnMap(x, y) = 1 <= x <= size && 1 <= y <= size

function checkTrail(x, y, reached)
	local c = grid[y][x]
	if c == 9
		push!(reached, (x,y))
		return 1
	end
	local score = 0
	for (u,v) in ((x+1, y), (x-1, y),(x, y+1), (x, y-1))
		if isOnMap(u, v) && grid[v][u] == c+1
			score += checkTrail(u, v, reached)
		end
	end
	return score
end

partOne, partTwo = 0, 0

for y in 1:size
	for x in 1:size
		if grid[y][x] == 0
			local reached::Set{Tuple{Int,Int}} = Set()
			global partTwo += checkTrail(x, y, reached)
			global partOne += length(reached)
		end
	end
end

@show partOne, partTwo