On 9/14/07, Ruby Quiz <james / grayproductions.net> wrote: > This week's Ruby Quiz is to write a simple utility. Your program should accept > an IP address as a command-line argument and print out the two letter code for > the country that IP is assigned in. You can find a database for the matching > at: > > http://software77.net/cgi-bin/ip-country/geo-ip.pl > > To keep the problem interesting though, let's write our programs with a focus on > speed and memory efficiency. Hi All, Here's my submission. It's almost exactly the same as Jesus'. I have a feeling everyone is going to have very similar code for this one. http://pastie.caboo.se/97332 os = ARGV[0].split(/\./) ip = os[3].to_i + os[2].to_i*256 + os[1].to_i*256**2 + os[0].to_i*256**3 f = File.open("IpToCountry.csv") # perform binary search on the file low = 0 high = f.stat.size while low <= high mid = (low + high) / 2 f.seek mid # seek to the middle of our search window f.seek -2, IO::SEEK_CUR until f.getc == ?\n # walk backwards until we hit a newline new_high = f.pos - 1 line = f.gets new_low = f.pos from, to, x, x, country = line[1..-1].split(/","/) if to.to_i < ip # we are too low, set new low to after this line low = new_low elsif from.to_i > ip # we are too high, set new high to before the last newline high = new_high else puts country; exit end end puts "no country"- steve