AOC-2023-1

partone.lua

local input = os.getenv("PWD") .. "/2023/1/input.txt"
local sum = 0

for num, i in io.lines(input) do
	local r = {}

	-- each line becomes a table of values
	for c in num:gmatch(".") do
		-- remove values that are not numbers
		local bit = tonumber(c)
		-- make a table out of those numbers
		table.insert(r, bit)
	end

	-- we only want 2 values in the new table, first and last
	local m = { r[1], r[#r] }

	-- make those 2 vales a single digit
	local n = tonumber(table.concat(m))

	-- add it to sum
	sum = sum + n
end

print("SUM: ", sum)