def display_recent
    load_recent

    puts

    (Problem.total).downto(Problem.total - 9) do |i| 
      puts "#{i} - #{Problem[i].title}" 
    end
  end
def display_recent
    load_recent

    puts

    (Problem.total).downto(Problem.total - 9) do |i| 
      puts "#{i} - #{Problem[i].title}" 
    end
  end
Displays the 10 most recently added problems.