counter.rb

#!/bin/ruby

filename = $*[0]
lines = {}
puts "Comparing #{filename}"
File.open(filename, "r") do |f|
  while (line=f.gets) do
    line = line.downcase.gsub(/\n/, '')
    lines[line] ||= 0
    lines[line] += 1
  end
end

lines.keys.sort.each do |k|
  puts "#{k}: #{lines[k]}"
end