def get_lines(filename) return File.open(filename, 'r').readlines end
def get_format(lines) return "%0#{lines.size.to_s.size}d" end
def get_output(lines)
format = get_format(lines)
output = ''
lines.each_with_index do |line,i|
output += "#{sprintf(format, i+1)}: #{line}" end return output end