#!/usr/bin/env ruby

if ARGV.size < 2 then
	puts "Usage: #{__FILE__} target denominator"
	exit
end

file = ARGV.shift
denom = ARGV.shift.to_i
i = 0
open(file).each{|line|
	if i % denom == 0 then
		puts line
	end
	i += 1
}