#!/usr/bin/ruby

require 'date'

def num_weeks(year = Date.today.year)
  # all years starting with Thursday, and leap years starting with Wednesday have 53 weeks
  # http://en.wikipedia.org/wiki/ISO_week_date#Last_week
  d = Date.new year, 1, 1
  if d.wday == 4 then 53
  elsif d.leap? and d.wday == 3 then 53
  else 52 end
end

puts num_weeks()