#!/usr/bin/ruby # # See ../README.md # # # Run as: ruby ch-1.rb < input-file # ARGF . each_line do |n| result = 0 seen_one = false n . scan(/[0-9]/) do |digit| result *= 9 if (seen_one) result += 8 elsif (digit == "1") seen_one = true elsif (digit != "0") result += digit . to_i - 1 end end puts (result) end