class Pair
　def initialize(name, contents)
　　@name = name
　　@contents = contents
　end
　def name
　　@name
　end
　def contents
　　@contents
　end
end
Dir.chdir(ARGV[0])
data = Dir.glob("[^.]*").collect { |file_name|
　f = File.open(file_name)
　begin
　 Pair.new(file_name, f.read)
　ensure
　 f.close
　end
}
data.sort{ |a, b| a.contents <=> b.contents }
i = 1;
while i < data.length do
　str = data[i - 1].contents
　if str == data[i].contents[0..(str.length - 1)] then
　　File.delete(data[i - 1].name)
　end
　i += 1
end