find duplicate city name for me.

anyduplicate.rb

#!/usr/bin/ruby
#encoding=utf8

cities = {}
open("/Users/venj/Desktop/city.txt").each_line do |l|
  city = l.split("=").last
  if cities[city].nil?
    cities[city] = 0
  else
    cities[city] += 1
  end
end

cities.each do |key, value|
  if value > 1
    puts key
  end
end