euler19.rb

   1 require 'date'
   2 require 'logger'
   3 log = Logger.new(STDERR)
   4 log.level = Logger::WARN
   5
   6 sundays = 0
   7 1901.upto(2000) do |year|
   8   1.upto(12) do |month|
   9     sundays += 1 if Date.new(year, month, 1).sunday?
  10     log.debug { "#{Date.new(year, month, 1)} is daynum #{Date.new(year, month, 1).cwday}"}
  11     log.info { "#{Date.new(year, month, 1)} is a sunday, making #{sundays} so far" } if Date.new(year, month, 1).sunday?
  12   end
  13 end
  14
  15 if __FILE__==$0
  16   puts sundays
  17 end
  18
  19 log.close