N = gets.to_i
R = gets.chomp.split

def value c
  case c
  when ?I then 1
  when ?V then 5
  when ?X then 10
  when ?L then 50
  when ?C then 100
  when ?D then 500
  when ?M then 1000
  end
end

def tot s
  s.chars.inject(0) { |a, b| a + value(b) }
end

def rev v
  s = ""
  (s << ?M; v -= 1000) until v < 1000
  (s << ?D; v -= 500) until v < 500
  (s << ?C; v -= 100) until v < 100
  (s << ?L; v -= 50) until v < 50
  (s << ?X; v -= 10) until v < 10
  (s << ?V; v -= 5) until v < 5
  (s << ?I; v -= 1) until v < 1
  s
end

puts rev(R.inject(0) { |a, b| a + tot(b) })