Outputs the n shortest lines from a file

shortest_lines.rb

num_longest = ARGV[1].to_i
longest_lines = []
shortest_len = -1

infile = File.new(ARGV[0], "r")
while ( line = infile.gets )
    unless line.length > shortest_len
      continue
    end
    
    longest_lines.push(line)
    longest_lines = longest_lines.sort {|a,b| b.length <=> a.length }
    if longest_lines.length > num_longest
      longest_lines.pop
    end
    shortest_len = longest_lines[-1].length
end

longest_lines.each do |l|
  puts l
end