#!/opt/local/bin/lua -- -- See ../README.md -- -- -- Run as: lua ch-1.lua < input-file -- for line in io . lines () do local result = 0 local seen_one = false for c in line : gmatch ("[0-9]") do result = result * 9 if seen_one then result = result + 8 elseif c == "1" then seen_one = true elseif not (c == "0") then result = result + tonumber (c) - 1 end end print (result) end